Ackchyually, all of the guardians have language implants except for Groot, and Thor has a power called All-Tongue. It is likely that none of them speak English except for Star Lord who is from Earth.
Yeah - tech in space and stuff. Makes you wonder though - all earth based adventures before they introduced GotG... Everyone speaks English. Like even when they busted up some peace accords - even the tribal warriors in Wakanda...
Stan Lee covered this in one of the old cartoons (fantastic 4 maybe) where he did intros, it was a fun little explain away for the "True Believers" P.I.P. Stan
No actually, they explained that in the movie. They all have a surgical implant called a Galactic Translator that fixes that exact problem. Does that help?
