The tooltip for fedipact says: “Agreed to block all communications (their blocklist is private)”
To me that says, they’ve agreed but it’s not confirmed that they’ve gone through with it because the blocklist is private. Blocked on the other hand says “All communications are blocked”
I haven’t tried these so I cannot comment on their quality. But this has a list. Of particular note is RetroArch, OpenEMU, and Gens as three FOSS options.
Edit: Also, alternativeto.net is usually a decent source for finding alternatives for specific software. Here’s the list for Kega Fusion alternatives. This has some more options than the other link I provided.