That porygon is just resized Big Porygon (boss) sprite, even though f*cked up one.
Resizing doesn't work as you think, at least not on sprites.
Also its color doesn't fit. Porygon(1) is a little bit lighter.
About Omastar, that is not a full remake, looks too paintish, in game it would look bad (Yoku learned at that point too (too light blue)^^)
About Omastar, that ain't a full remake