There are 3D ponies who go about their business. There is an evil villain who wants to do something evil, but cannot get out of captivity. He has a henchman to whom the villain promised something, and he, licking the villain's ass, tries to please him
But the henchman is not familiar to the main ponies and is considered a friend in their circle….
Since Twilight is shown as small, the events with Opaline apparently took place after Twilight's coronation, but before her tall version
Opaline I think related to Flurry Heart
Maybe she's a sister or daughter
In the cartoon "Filly Funtasia" the henchman communicated with the antagonist through a mirror…
Doesn't it remind you of anything?