This happens to be trending on Hacker News right now: https://www.ycombinator.com/blog/startup-school-east-boston/
they also have a cofounder matching program https://www.ycombinator.com/cofounder-matching
Probably nothing like this exists for EA-specific matching though IDK
https://forum.effectivealtruism.org/posts/q2PwXNsXsfDYkxeHb/aim-ce-new-program-founding-to-give-apply-now-to-launch-a
seems relevant