If you had asked a while ago I would have recommended Super Mecha Champions, an anime styled third-person Battle Royale game where you could call in a mech or fight on foot as a pilot. Sadly, the servers shutdown, so I can’t play it anymore. The game had gacha elements for cosmetics, but characters and mechs were earnable in game. The gameplay was fun too, I really miss it. Which feels crazy for me to say about a NetEase game that started on mobile. I guess they needed more server hardware and developers for Marvel Rivals.

You might try M.A.S.S. Builder, although it is more similar to Gundam than MechWarrior. It is also anime styled, but the anime characters aren’t really on screen for very long compared to your own mech. The mechs are more humanoid in appearance and are insanely customizable, down to the bare frame even. It has some multiplayer though it is primarily designed as a singleplayer game.

There is of course, MechWarrior 5, I think Clans is new, and MechWarrior Online has what, 16v16 or 8v8 matches?

Mecha Break might be one to look into. I haven’t looked into it took much myself but I have heard good things about the gameplay. I think its a 5v5 PvP game.

As greatly pained as I am to say it, mech games are a tiny niche. One that suffers from “the mech curse,” which is basically that a game gets popular for a month and then dies off hard.