Mutants and masterminds?

I hope I understand your question correctly, please let me know if I'm off base. At the moment the Core Rulebooks for Mutants & Masterminds are not available on Roll20. The best folks to talk to about getting them released here would be Green Ronin Publishing.

While I can't speak to the decision making process on these items specifically I can say that there are several items available in the marketplace that do not have a corresponding compendium available for sale. Ordinarily the idea here is that if there's a character sheet available then having a module available saves a ton of prep time for anyone who has access to the rules whether in cases like this where they're freely available online or if the GM and/or players own physical or PDF copies of the core books.