You need, at minimum, somebody capable of ripping the game text and inserting the translated stuff, somebody who can edit game CGs featuring text, and a translator. Depending on the specifics of the game and the team working on it, you might need more or fewer people (a translator who can hack reasonably well, for instance, or a game that stores its text in a really easily edited manner). You DON'T want a ton of translators. The final product will end up flowing really oddly with several different writing styles unless you have a really great editor(s).
For instance, the Seinarukana translation team has a team of 1 translator (along with two who quit partway through), 3 editors, 2 graphics guys, and a coder. The Kara no Shoujo translation had 1 translator, 2 editors, 1 image editor, and a dedicated subtitler.
Paid/commissioned fan translations aren't really a thing. The closest I can think of was Aroduc's Kickstarter drive a couple weeks ago, which got shut down by the IP holders within a couple days.
So you probably can't put together a translation team from here, and commissioned translations are pretty unprecedented to my knowledge (and a legally pretty grey area). Your best hope is an existing translation team picking one of these games, which is... unlikely. Most of them are, so far as I know, nukige (mostly porn). Nukige, as a rule, don't get fan translated (because there's nothing really worth translating to most people).