You just hate Mexicans don't you.
On the subject of bad fightan game VAs, Captain America's newest voice actor in Marvel vs Capcom 3 is abysmal. Considering how they managed to get Josh Keaton and Steve Blum to reprise their roles as Spidey and Logan, how hard could it have been to get David Hayter, Justin Gross, or Brian Bloom to voice him again?
In a similar vein, there is Mignon Beart from Maximum Impact. I can tolerate the MI dub voices because most of them still ooze of that classic SNK cheese I like, but Mignon's VA clearly tried to pander to her moe appeal. But it doesn't work here when she's a filler character with very few practical uses.
Also, NoA saw fit to have some porn actor voice Mia in Fire Emblem Radiant Dawn. There wasn't a lot of voice work in that game, but that's still no excuse to make the Greil Mercenaries sound so lifeless. Mia just happened to get stuck with the most appalling, unfitting voice in the game. I'm talking Bible Black-bad levels here, and she only had like 3 lines.