Many movie makers have their favorite actors they like to work with, and the DC boss James Gunn is no different. Two examples of this are Chukwudi Iwuji and Michael Rooker, who has shown up in both Gunn's DC and Marvel efforts, and it seems like more actors he has previously done Marvel with is about to show up in the DC universe (DCU).
When a user asked Gunn on Threads if the Guardians of the Galaxy actors Chris Pratt and Pom Klementieff could show up as themselves in Peacemaker, the DC boss and director replied:
"There are reasons I wouldn't want either of those actors to play themselves in the DCU!"
The only reason we can think of as to why this wouldn't work, is that they will play other characters in the DCU, something Klementieff herself has implied previously (and Pratt is rumored to play the character Booster Gold in a TV series).