Everyone talks about Street Fighter or Tekken, but let's hear it for the weirder, unique, underrated, or forgotten fighting games out there.
My favorite is a Gundam game. Federation Vs. Zeon and it's sequel, Gundam vs Zeta Gundam, made by Capcom. The original games in the Gundam Versus franchise of games. imo the series was at it's best when it was handled by Capcom.
I still play Bushido Blade to this day, it's fun as fuck.