mega mane qc check

[OVERIEW]

You note that Mega Mane is weaker offensively than many other Megas, but point out that Mega Mane is used as a support pokemon rather than an offensive pokemon like Mega Metagross is.
Mega Mane's Intimidate is certainly very handy for switching into things like Metagross and Incineroar, but it is not a switch in to perhaps the most formidable physical attacker in the format, Zygarde
Instead of saying "its coverage lets it hit the tier", maybe go for something along the lines of "Neat coverage moves of Overheat/Flamethrower give it a offensive niche over other Electric-types like Tapu Koko.
[SET COMMENTS]

[MOVES]

When mentioning Mega Metagross as an overheat target, perhaps change the format of the sentence to "Overheat hits Grass-types like Tapu Bulu and Amoonguss, as well as Steel-types such as Mega-Metagross and Ferrothorn. All of those Pokemon take Mega Manectric's other moves quiet well."
Along the same lines, when talking about HP Ice, not that Zygarde and Landorus-T totally wall any set without HP Ice, which sells home its niche more than Zygarde and Landorus "not minding" its other attacks.
You only say HP Ice can be used with Overheat while dropping Snarl, but you have it slashed behind Snarl and Overheat on the set. There should be more detail about the pros and cons of dropping either Snarl or Overheat for HP Ice.
[SET DETAILS]

Small thing, but generally when you have maximum investment into a stat, you can phrase that part of this section by saying "Maximum Speed investment with a boosting Nature ensures Mega Manectric outspeeds x and y"
No need to transition into the defensive benchmarks with "on the other hand", you aren't changing anything or taking anything away from the point you made about its speed. Also, the spread allows it to live Lele Moonblast OR +0 Mega Metagross Stomping Tantrum, not both of those attacks as "and" implies.
I would say Lightning Rod is a necessity, using its pre-mega Lightning Rod support is a large part of successfully using Mega Manectric.
[USAGE TIPS]

Mega Manectric's Intimidate is not immediate, it has to mega evolve first. This is especially important because switches occur before mega evolutions, so you may not get to Intimidate the pokemon you wanted to.
Note that when preserving Manectric for the late game, you are generally doing so to ensure more support for an actual win condition, instead of relying on Manectric's speed to win you games. The only time you are really saving Mega Manectric for damage is if your opponent has a Ferrothorn or something you cannot deal with otherwise.
You aren't totally left helpless if a Zygarde switches into a volt switch, as you will still be able to pivot out next turn on the other slot, hard switch, or hp ice the Zygarde, but it would be more correct to say that a Ground-type switching in on a Volt Switch leaves Manectric vulnerable to damage it wasn't planning on taking that turn.
[TEAM OPTIONS]

When talking about forming a VoltTurn core, saying something like "Pokemon with U-turn like Genesect and Incineroar can synergize well with Mega Manectric, allowing for constant pivoting and a continually changing board state" would be more clear than the way it is currently worded.
You can't use Mega Charizard Y with Mega Manectric.
Mega Manectric teams require ways to deal with opposing Dragon-types like Kyurem-B and Kommo o, Tapu Fini and Genesect are strong choices for this role.
The last part about Gothitelle doesn't read very clearly, a more precise way to word it would be "Gothitelle traps Pokemon that have had their stats lowered by Intimidate or Snarl while also being able to reset opposing Trick Room.
[OTHER OPTIONS]

Instead of saying using Overheat forces Manectric out, say that it drops its damage output considerably. You can still click Snarl for your teammates sake at -2, or Overheat something again for a lesser amount of damage.
[CHECKS AND COUNTERS]

I would say "Dragon-types" over just Kyurem-B, Soundproof Kommo-o avoids snarl and easily takes HP Ice while setting up and knocking out Manectric with Clangorous Soulblaze.