I think that Sailor Galaxia and Akio have to much things in common , in their 90s anime version only.
1.They both were good persons once , Sailor Galaxia was a legendary senshi that fought against the Chaos and Akio was a prince that helped all the ladies in dimstress, but then they got corrupted and got transformed into villains.
2.They both separated themselves into two entities when they got corrupted , Galaxia fred her star seed from her and created chibi chibi , which I consider that was the good side from her ,just as Akio had her good side , the Prince Dios , resguardeated in the floating castle.
2.5. There is a theory that says that Chu Chu was also a separated part of Akio , his name is even similar to Chibi Chibi , if that theory is true , it could add even more similarities, since they both are characters that only say their names .
3.The good alter egos of the villains help the main protagonts , just as Chibi Chibi helped Sailor moon , the prince Dios also helped Utena various times by descending from the castle in order to give to Utena the power to give her final strike .
4.They both had an altered backstory , Kakkyu thought that an legendary senshi sealed the Chaos away a long time ago without doing anything bad, she didn’t knew that the legend of the sailor war was altered , and that the legendary senshi wasn’t that good and holy heroine that the legend claimed her to be , that reminded me to Akio when he showed to Utena and anthy , and altered backstory of him , he portrayed himself as an hero that everybody loves , and Anthy as a jealous witch that wanted him to herself , Akio deleted the part of the story where Anthy tried to save him just as in the legend of the sailor war it was deleted the part where Galaxia sealed the Chaos inside her body , even though I don’t know if it was Galaxia itself who altered her backstory or it was the pass of the time ,since we didn’t had too much details about how that legend got to be known by Kakkyu , but I think that it is still a similar aspect to Akio.
Well , that’s all , I wanted to share this cause I really think that this characters share to much similarities in their villain story , and I had never saw someone comparing Galaxia with Akio ,well have a nice day bye .
PS, Off topic but I also compare Touga with Angel Dust from hazbin hotel , just saying because kasumigenx watched that series .