UFC fighters can compete in ADCC because there is no striking unlike Combat Sambo.
They always have been allowed to.
I would love to see Maia in ADCC because with Jacare not in it I want one of the better grapplers in it since Marcelo seems focused on Dream WW GP and Roger is doing the Super fight.
On a positive note Pe de Pano and Werdum will be competing.
And Fedor also which IMO will lead to him losing to either Pe de Pano or Werdum.