I hate to tell you this, but there were no crystal (glitter) variants made for the Spitfire/Sweetie Drops wave. I wish there were because they would have been great!
Glitter variants of Sweetie Drops have been found already - you can see one in Brony Galore's sales thread, and Funko themselves have said (in a reply on their facebook page) that both will be available as glitters.
WAIT! BREYER! I wish to addd in a trade too for the twilight sparkle! My pinkie pie vinyl with blind bag ponies of any kind for it. Please I've been looking for a twilight sparkle vinyl-I don't care if its normal or glitter, but I need it for my collection. Pleasseee....