Honestly: Pitch yourself. Email an editor at your website of choice with a sample of your work (or two) and let them know you wanna cover fighting game stuff if it pops up in their queue.
You will likely not get paid for this, however.
A lot of writers at gaming websites don't really have a lot of time to play the games they report on, much less play enough to have a very deep knowledge of the game's mechanics, much less the amount of knowledge needed to break down something like what happens in a high-level fighting game.
If you're able to cover that sorta stuff, make it readable, and you're essentially volunteering to do it, that's less stuff on their plate, at no cost to them. They'll probably consider it.