That's not what I mean, though. (Sorry for late reply - I am bad at navigating the notifications on this site lmao)
I don't want my skin to be transparent in-game. Minecraft already prevents that - in-game, any transparent bits on the first layer get blacked out.
I want to upload transparent skins on Planet Minecraft, so when skins are downloaded, a user can simply drag it over another skin in an image editor without having to hunt down the black or white pixels and erase them.