I used some time to collect all the evidence I can find of Artia being connected to the spam and the abuse. It's long so please take your time reading.

Artia, livestreaming as Artia, says that she participated in a anti-Taiwan harrasment campaing and being proud of it, streamed May 20: https://www.youtube.com/watch?v=ul8E90RHAsI

Wiki about the forum she mentions (Di Bar): https://en.wikipedia.org/wiki/Li_Yi_Bar
The wiki also has information about the 2016 attack on Facebook that Artia mentions.

On October 21 Artia along with Doris watch "Wolf Warrior" on bilibili (https://live.bilibili.com/record/R1qx411c7fZ) (https://web.archive.org/web/20201114142445/https://live.bilibili.com/record/R1qx411c7fZ).
Wolf Warrior is a nationalist Chinese action movie that coined the term "Wolf Warrior Diplomacy" that is an aggressive and confrontational diplomacy used by Chinese diplomats (https://en.wikipedia.org/wiki/Wolf_warrior_diplomacy).

Artia and Civia talked about the allegedly leaked Aqua Cover of “Take Over” that was used as a rally cry for the spammers to continue with their actions. I can't find any HololiveJP, HololiveEN, HololiveID talking about the song.

Artia: https://twitter.com/Artia_OW/status/1320416576617672706
(https://web.archive.org/web/*/https://twitter.com/Artia_OW/status/132041657661767270)

Civia: https://twitter.com/_Civia/status/1320420560787116033
(https://web.archive.org/web/20201025212839/https://twitter.com/_Civia/status/1320420560787116033)

https://twitter.com/_Civia/status/1320423299470471175
(https://web.archive.org/web/20201026001853/https://twitter.com/_Civia/status/1320423299470471175)

The talents pages in bilibili “hijacked”, posting about the song and the spam bot:
(https://old.reddit.com/r/Hololive/comments/jk7atj/the_jp_girls_bilibili_channels_were_hijacked_by/)

Artia following and interacting with "@ywwuyi" that supports the harassment of Coco and is linked with the NGA board where harassment discussion is found.

Mutual follows of ywwuyi with Artia and Civia:
https://en.whotwi.com/ywwuyi/mutual_friends
(https://web.archive.org/web/20201114065224/https://en.whotwi.com/ywwuyi/mutual_friends)

Tweet from Oct 18 (liked by a bunch of twitter spammers, day of Coco's return Asacoco):
https://web.archive.org/web/20201107234403/https://twitter.com/ywwuyi/status/1317943492862070784

Tweet from Oct 19 (liked by Artia, day of Coco's return stream):
https://web.archive.org/web/20201107234541/https://twitter.com/ywwuyi/status/1318122019280482304

Image prove of Artia like: https://imgur.com/a/i9oSoWb
Video prove of Artia like: https://streamable.com/e/fuwq70
(https://web.archive.org/web/20201114185731/https://streamable.com/e/fuwq70)

As of 14/11 Artia still has this tweet liked, you can check it yourself.

Tweet from Oct 25
https://web.archive.org/web/20201105024607/https://twitter.com/ywwuyi/status/1320524295295004672

Translate by another user
(https://old.reddit.com/r/VirtualYoutubers/comments/jnv0x1/artias_opinion_on_chinese_nationalists/gb5b6zz/)

"FROM MY LIMITED MANDARIN: "These few days the traffic in the Vtuber section of NGA is even higher than the Genshin section, righteous men picking up the unicycle (the clown is using the unicycle, a symbol of sorts for the spammers I think), turning into 网暴man（probably meant spammer? ) for their beloved woman. 虫皇 (what the spammers call Coco), is this the world you want? I really like this sentence of yours, fxxk u and never come back. (Coco had this in her stream end card)"

Tweet from Oct 26, message of encouragement to continue the spam
https://web.archive.org/web/20201026031614/https://twitter.com/ywwuyi/status/1320530300485595138

Interaction between the two on Oct 23:
https://twitter.com/Artia_OW/status/1319756428999995392
(https://web.archive.org/web/20201104192734/https://twitter.com/Artia_OW/status/1319756428999995392)

Interaction on Jul 15:
https://twitter.com/artia_ow/status/1283518953541603328
(https://archive.vn/2Ft8m)

If you search on twitter "@ywwuyi @Artia_OW" you can see other users commenting on a interaction dated to Oct 25 but the tweet was deleted.

Archive of others commenting on the interaction:
https://web.archive.org/web/20201026011544/https://twitter.com/Gisela38730015/status/1320530238145609728
https://web.archive.org/web/20201026103515/https://twitter.com/mononokapr/status/1320561516349812738
https://web.archive.org/web/20201026070005/twitter.com/th12450/status/1320512546944675840

Artia past life/alts being: 猫铃五度音/ Elyonow / Ellie_channel

Image with a summary of the evidence: https://i.imgur.com/IYkOnSk.jpg

All the links in the image:
https://twitter.com/tskmnzrhld/status/1310276331481882625
(https://archive.vn/HC0le)

https://twitter.com/tskmnzrhld/status/1310308451860525058
(https://web.archive.org/web/20200927205714/https://twitter.com/tskmnzrhld/status/1310308451860525058)

https://twitter.com/tskmnzrhld/status/1310308654642593792
(https://web.archive.org/web/20201114095348/https://twitter.com/tskmnzrhld/status/1310308654642593792)

https://twitter.com/tskmnzrhld/status/1310309023842000898
(https://web.archive.org/web/20201114095556/https://twitter.com/tskmnzrhld/status/1310309023842000898)

https://warosu.org/jp/thread/S26978958#p26981645
(https://web.archive.org/web/20201114094427/https://warosu.org/jp/thread/S26978958#p26981645)

https://www.youtube.com/c/ArtiaHololive/
(https://web.archive.org/web/20201114100844/https://www.youtube.com/c/ArtiaHololive/)
If you click on discussion page of the channel you will find a comment redirecting to artia's bilibili, made 3 months ago (2 month prior to any drama): https://archive.is/DPUz1

https://web.archive.org/web/20201001052211/https://twitter.com/Elyonow
https://web.archive.org/web/20200927181421/https://twitter.com/Elyonow/status/1310259997582868481

Tried to archive search results of Twitch streams/clips thumbnails of Elyonow but it doesn’t work. I will link the images URL. Take notice of the character.

https://encrypted-tbn0.gstatic.com/images?q=tbn%3AANd9GcRTpSb34lfvVsxdAuvZoRXzHoGbPtdnmrUuUw&usqp=CAU
(https://web.archive.org/web/20201114090543/https://encrypted-tbn0.gstatic.com/images?q=tbn%3AANd9GcRTpSb34lfvVsxdAuvZoRXzHoGbPtdnmrUuUw&usqp=CAU)

https://static-cdn.jtvnw.net/cf_vods/d2nvs31859zcd8/b2d2b20127b9302fc822_elyonow_39758806910_1600464808//thumb/thumb0-276x155.jpg
(https://web.archive.org/web/20201114090605/https://static-cdn.jtvnw.net/cf_vods/d2nvs31859zcd8/b2d2b20127b9302fc822_elyonow_39758806910_1600464808//thumb/thumb0-276x155.jpg)

Image that shows the google result: https://imgur.com/a/GAuvESY

Video of her talking, showing the avatar and twitter link (@Ellie_channel)
https://files.catbox.moe/i1h2kb.mp4
https://web.archive.org/web/20201114091248/https://files.catbox.moe/i1h2kb.mp4

https://web.archive.org/web/20190903051825/https://twitter.com/Ellie_channel
https://web.archive.org/web/20200418070058if_/https://twitter.com/Ellie_channel
https://web.archive.org/web/20201103223046/https://twitter.com/Ellie_channel

Artia is 猫铃五度音

Artia weibo is https://weibo.com/u/1748729994.

In this archive the weibo account posts a Elyonow/Ellie character drawing, scroll until you found it.
(https://web.archive.org/web/20200611032357if_/https://weibo.com/u/1748729994)

In this archive the account posts another character drawing, scroll to the bottom.
(https://archive.vn/izuyN)

More archive showing drawings of Elyonow/Ellie. (https://archive.vn/YAPaO)

A Pixiv account that has some of the drawings in the weibo: https://www.pixiv.net/en/users/13966815/ (https://archive.vn/zg0yL)
Illustrations showing the Elyonow/Ellie: https://www.pixiv.net/en/artworks/82652917 (https://archive.vn/FFsqy)

Douyu with the username 猫铃五度音 and profile pic similar to Elyonow/Ellie:
https://www.douyu.com/5027311 Archive from Nov 1 2020 with same information:
https://web.archive.org/web/20201101033829/https://www.douyu.com/5027311
Archive from Jul 14 2020 with same infromation:
https://web.archive.org/web/20200714035814/https://www.douyu.com/5027311

Baidu, a Chinese forum, discussing that Artia is 猫铃五度音. (https://archive.is/32BWG)

Archive showing that Artia posted “Hold the bottom line, keep going” in weibo. (https://archive.vn/DogXF)

Artia admits saying “Hold the bottom line, keep going”. She also indirectly admits being two faced, for she says one thing in public and another in private.
(https://web.archive.org/web/20201103210555/https://twitter.com/Ellie_Channel/status/1323733079886688256)

Artia says that she doesn’t want to take dirty money (work for hololive) in weibo. (https://archive.vn/2OFCU)

A Chinese post in Baidu gathering evidence that links Artia to Li Yi Bar, the forum that ignited the 2016 anti-Taiwan harassment campaign and that Artia mentions in the first video. http://live.baidu.com/p/6697065616
(https://web.archive.org/web/20201114140837/http://live.baidu.com/p/6697065616)

Wikipedia explaining the forum: https://en.wikipedia.org/wiki/Li_Yi_Bar

This is the information I am less sure of.
Artia discord server discussing the usage of the spam bot.
https://pastebin.com/P5683NU7
https://www.youtube.com/watch?v=8BK7pluFl3I