Quote - I much prefer V3 to V4, and it makes me very sad that there's pretty much nothing being made for her any longer.

I'd see this as an opportunity to learn how to make things for her yourself. Imagine the satisfaction you'd get out of it!
Also, you can obtain any number of tools to convert V4 items to V3... personally, I like using Blender3D for that purpose, and Obj2Cr2 to make the modded item into a conforming clothing again from the obj file. Amazing how much you learn about mesh having a good look at it in Blender3D. I've learned to admire some people's work... Fabiana stands out as a premiere modeller!

Besides, this gives you a chance to tweak a thing or two and make the item even better than before. Can't do that with Fabiana's mesh though: impossible to improve on perfection.

Monterey/Mint21.x/Win10 - Blender3.x - PP11.3(cm) - Musescore3.6.2

Wir sind gewohnt, daß die Menschen verhöhnen was sie nicht verstehen
[it is clear that humans have contempt for that which they do not understand] 

Metaphor of Chooks