I happened to stumble upon these while watching Transformer reviews by our very own Peaugh.

YouTube - osro1113's Channel

There are 22 different Transformation animations in all. Almost all the robots from the first two films are covered, including combiner forms.

There is also an IRON MAN title sequence and a funny hand drawn animation of a sockpuppet that comes to life once worn by it's owner. 24 videos in all.

This individual is quite talented. From what I've been able to gather, the creator behind all these is SeoRo oh. Unfortunately for the time being, they won't be making any more videos because in the country they are from (where exactly? I do not know), they have to join the military(Army) when they turn 20, and stay in the service for almost 2 years (22 months). This artist's latest unfinished/w.i.p. piece is the entire Movie Constructions and them forming into Devastator.