He-Man and Battle Cat are turned back into Prince Adam and Cringer when the enter the portal to go to Trolla, but when they return to Eternia, after finding a way to turn back into He-Man and Battle Cat, they are not reversed once more.
When Dree Elle revives, she is still wearing the draining machine cap on her head, but the metal rod with wires that was attached to it has disappeared.
Orko and Dree Elle leave Eternia in the pyramid, but arrive on Trolla without it. Since Dree Elle came to Eternia by hiding in the pyramid, it should be there with them.
On the planet Trolla, Prince Adam realizes everything works backwards. To become He-Man, Adam says "Greyskull of power the by"! However, he still says "I have the power" the normal way. Surely, that would need to be in reverse too since everything else is that way.
As Adam, Cringer and Orko approach Dragoon's fortress in a wide shot, for some reason Adam is shown in silhouette but the others are not.
After He-Man, Battle Cat and Orko return to Eternia, Orko is floating with his outfit gently swaying as usual, but for one frame his outfit is misaligned, leaving revealing black outlines that should not be there.
During the transformation sequence in front of Castle Grayskull, Cringer's nose is a lighter shade of green than usual in his close-up, and the Sword of Power doesn't make any of the usual sounds when pointed at Cringer.
When Adam turns his head to Orko after being reunited on Trolla, his neckline is off for a couple of frames.
Adam laughs with the voice of He-Man after Orko's pyramid sprays water in Man-At-Arms' face.