I have the 'unofficial' Maitreya file made by a Youtuber and it is a plugin for Avastar. I
think it is this one:
Link but there was quite few around pre-bento age. Often you heard the fan-made kits were better than actual one provided by Maitreya. Never looked into it much as turns out that standard SL body skeleton is best to work around with all bodies - you usually just move few bits or weight them differently.
I do applaud anyone looking at SL now and going all excited about creating because yep ... also started with that intent and I fondly recall camping around a mall to earn 300 Lindens to rent a stall to sell my textures. No one ever learned how truly genius I was at those tartan, flexi kilts because I found a job as an event manager (and that was pre-current event age where it worked more like a proper media job as it got me into a foreign uni for audiovisual editing after all
) and spent all my money on guns. Alongside me, also starting out was a scripter that took apart every linked object and reassembled it into spiders when he learned I hate them. He did not suck unlike me but no idea what happened of him.
If current teen me seen current SL, I would react same way as I do to IMVU or VRChat and run away very fast. It is just not ... that crazy, chaotic, inspiring environment where people of all skills have a place any longer. So this post already shows that as this person researched unlike when I started and just wanted to be a ~fashion designer~. I did eventually find my new media niche that is probably still akin to what I ended up doing in IRL (.... editing loads of photos that is...).
I guess best tip for currently starting fashion creators is to try maybe with templates first and get to know them in their favourite editing program. Play around and eventually with trial and error you will make something you end up liking. Also best to try all those bodies and scope their options beforehand so you know what you want to do for each.
I think all bodies should have dev kits and be moddable as yep - people are going to make horrid stuff and mistakes but that is ... where the fun actually is.
Bonus: I did make a big sell on a 100L outfit I made. One sale that is. This one:
Link . And none of my kilts ever sold, I mean ... look how great they were and even came with a belt:
Link.