oooh man, Naming them to fit the Original Name is hard, since I don't think their name should ever change much if they were to Genderbend, mind you Genderbend characters is supposed to be their gender change, Not the whole Personality.

Hitch Trailblazer as Peach, Her name is the most hardest to match due to "Hitch" Have nothing that match the meaning to what she does and since G5 is not following most of what G4 naming style, I will name Her Peach, since Peach sound like Hitch. Overall, her look and Personality still matches her Male counterpart, But her Hair should be in Tie up ponytail and neat ish, So no long like fluttershy or messy like pinkie.

Sunny Starscout as Summer, Same like Peach, His name is the 2nd hardest to name, since "Sunny" Is a unisex name, While Summer is more toward Feminine name, I would dare to say why not? He having a female name is kinda cute. Overall, His look and Personality should still match His Female Counterpart and I made His hairdo look alot like Argyle since He will totally look alot toward his dad.

Izzy Moonbow as Isaac, He was the Easiest to name and Redesign, While Izzy have like messy mane that is long. I would think Isaac would have the same
Overall, His look and Personality should still match His Female Counterpart. While I think Isaac having a small facial hair look fitting on him

Pipp Petals as Pippin, Why would I still use Pipp name in her male counterpart? Well, you can still call him Pipp as a nickname. Overall, His look and Personality should still match His Female Counterpart. Now His Hair was tough to draw because I still want to use the same elegant hair without making it long or silly. So I settle with slick back hair styles, singers like Frank Sinatra or any singers from 30s to 50s.

Zipp Storm/Zephyrina Storm as Zephyrus, same like Pipp, Zipp is a nickname. not her full name, so Her male counterpart would still have the same. Overall, His look and Personality should still match His Female Counterpart. Heck His hair still stay the same just maybe shorter in the back, but his body is alot bulkier look same with Isaac.