This is subtle.
Legends are famous stories that may be based on real characters and events, but who can say for sure whether Achilles really slew Hector? So the legends may not be true. But the legends themselves exist, so they are real.
Real and true would seem to compliment each other but the way you're writing "It is real what he said" sounds slightly odd, as if it's said by a non native English speaker. "It's true what he said" or "What he said is true" or similar variants sound okay. Ditto for "What he said, it is real." (dramatic corny dialogue in a horror story, maybe) although again it has that non native English vibe, to me.