To Play in eu:
https://signup.leagueoflegends.com/en/signup/index in region select " Europe"
Open folder:
Riot Games\League of Legends\RADS\system
JaKoClubS> You have to change launcer.cfg locale.cfg and system.cfg
[9:21 AM] <JaKoClubS> launcher.cfg*
[9:21 AM] <JaKoClubS> launcher needs to be this for eu
[9:21 AM] <JaKoClubS> gameProject=lol_game_client_sln
[9:21 AM] <JaKoClubS> airProject=lol_air_client
[9:21 AM] <JaKoClubS> airConfigProject=lol_air_client_config_eu
[9:21 AM] <JaKoClubS> locale needs to be this
[9:21 AM] <JaKoClubS> locale=en_gb
[9:22 AM] <JaKoClubS> and system
[9:22 AM] <JaKoClubS> DownloadURL=l3cdn.riotgames.com
[9:22 AM] <JaKoClubS> DownloadPath=/releases/live
[9:22 AM] <JaKoClubS> Region=EU