I would laugh if it uses the same sprite style and recycles the same sprite sheets.
I doubt they're gonna recycle their assets in Freedom Planet 2 going by how the characters look now on the official website
, and the sprites in sequel looks more detailed than before.-EDIT-
Vegeta and Piccolo (Christopher Sabat) are gonna be in the game! Yea!-EDIT 2-
Here's a screenshot of what the sequel could look like that was posted when Galaxy Trail made their announcement.