The phrase “You ready Return” isn’t a grammatical error; it’s regular present tense of (pro)noun - verb - object.

It’s the same as “You ready (the spell) Return”, with the part in parentheses omitted. “The spell” is just implied, and therefore omitted; which is fairly common in English.


As for your other concerns; I have to see examples. FFXIV uses a lot of Ye Olde English speak, so words and phrases that sound odd even to native speakers aren’t all that odd, since the localization team is going for a sort of archaic feel.