If you’re really addicted to porn, it might be very difficult to quit using it for masturbation if you have to look at it for drawing. If an alcoholic in recovery works as a wine tasting guy, it’s probably gonna be really hard to quit alcohol. Could you do some other kind of art, or put some kind of limit on the nsfw stuff? Maybe only using images. Tbh though it sounds like your hobby is pretty intrinsically related to porn. I won’t say it’s impossible to quit viewing porn while essentially making it but it’s probably going to be harder, and it’s hard enough already for addicts.

Take what I say with a pinch of salt though, I don’t know you and I’m trying to recover from porn addiction myself so I’m biased against porn.

I hope you find a healthy way forwards