I get the worry about art theft and AI and stuff, but putting your watermark all over it is like... protecting your car by planting anti tank mines in your driveway. Yeah, nobody's gonna steal it, but now everyone just sees your driveway as a minefield.
Might I suggest subtly hiding your watermarks somewhere? Like some really inconspicuous place. Fun fact: Matt Groening does this with homer simpson (his ear and hair make up an M and a G)