@liaizon Hey, Lemmy's license is what I could guess GNU Afero, along https://github.com/LemmyNet/lemmy-ui/blob/main/src/assets/icons/favicon.svg file (used on the README). But each time I used Lemmy, I had comments about controversies about Lemmy's creators. So far, no report about the accusations on https://en.wikipedia.org/wiki/Lemmy_(software), so hard to know what's true or not. I prefer to not touch at the moment and let time clarify.
For PixelFred, I haven't found a clear license so far, all I have is https://github.com/pixelfed/brand-assets/tree/master , and nothing is mentioned.