“Please hold while we figure out what to put here!”
Canon for The Lusty Seapony separates from the show around the end of Season 3. We are presently approximately 8 years after the events of MLP:FiM.
Timeline Divergence : The Lusty Seapony's timeline split from MLP:FiM canon somewhere during Season 3. As such, Twilight Sparkle is a respected and admired unicorn, protégé to Princess Celestia and Headmistress of the Ponyville Library. Not an alicorn princess. The tree library is still present in Ponyville as well, complete with annoyingly indestructible owl. Individual elements of Season 4 and later material may creep in at various points, but Twilight Sparkle being a Princess is not one of them.
Equestria Girls : Pending discussion of the playerbase, the Equestria Girls movies are not considered to be canon. There is no mirror to a world full of anthro ponies. There is a mirror to a castle full of
horrible exciting monsters, but Ostfriesen is not EqG!Earth. It's better.