So I copied all my game folders (not steam backup through steam) there is no way to add them back to steam without re downloading? 
put it in the install directory. if you're using a standard setup it's "C:\Program Files\Steam\steamapps\common\Company of Heroes 2". if there isn't a directory then make one. steam (unlike origins) will automatically detect the files.
that's why i brought up multiple HDD/SSDs btw, i have all (~~600GB) of my games on D:\ and when i do a reformat i just have to reinstall steam and it automatically finds everything.