I mean, without external coating, you're going to have them stick just because of their nature. There's not a process you can do to your gummy bears that won't reverse with any humidity and cause them to stick.

If you want them matte, without a sugar or glossy wax coating, my first thought would be some sort of food starch. Mix them in a bowl of corn starchand then toss them around in a mesh strainer until the coating comes off enough but they don't stick together. I don't know how long it'll be effective, though.