SHORT AND CONCISE: SKINS WILL BE IN THE GAME.
LONG AND DETAILED:

What are skins?
Are they the same as costumes?
Can we mix-and-match skins with costumes to make a customizable plant?
Will there be skins for zombies in the Online Verses mode?
These will be the questions that I will be answering in this devlog.

		
			Skins, in PvZ3, are the modified looks of a plant that will look different, but otherwise have no effect on the plant's strength and ability. Skins are different to costumes, because costumes will modify the looks by adding masks, and hats, but not the plant's entire body or look. As well as that, costumes will also give the plant an extended ability, which I want to keep a secret. (Imagine PvZ2: Chinese)
I have decided not to allowing "fully customizable" plants, for same reason as one of the reasons of the delay of the game (partially). The reason is SPRITES. Sprites/avatars are images that change, and are particularly hard to make hundreds of. If I allow mixing and matching, I would have to rework the costume system, by making them NON-SEPARATE sprites. And I will not do that!
"Will there be skins for zombies in the Online Verses mode?"
To that I will say... there will NOT. Zombie skins would only be used in Online mode. At most, Zombie skins will depend on which "map" you are playing in the mode. This is because there are multiple names & sprites for a zombie which works the same, for example the Buckethead zombie.
Overall, I am excited for this idea, and that I would love to bring this idea to life, as y'all have asked for it, ever since my MariGOLD sprite. 
		
	

Have a good day!