No, its copyright and intellectual property infringement. Besides, its quite hypocrite for you to demand be respected as an artist when what you're doing is actually disrespectful
Just because you see something on the internet, doesn't mean you get to make messy lines on top of it and call it yours. You know anyone can fill a report to Webtoons and get your content removed for manipulating intellectual property that doesn't belong 100% to you. Because lets be honest, without using other people's works as foundations I hardly doubt you can make something somewhat decent in anatomy or even composition, try making something without using others as ladders.
Appropriationism is one thing, but what you've been doing is not that, just a poor attempt of scribbling on top of other people's work with an inferior quality and damaging the original works. (You even learn this at Art School or a Graphic Design course, which I would recommend you to assist, you really need it)
And yes, both copyright guidelines apply for both Webtoons and Tapas.
Insulting me like a flying monkey is not an argument, but just in case, your novel may be at risk of copyright infringement thanks to the fraudulent work of your artist, its up to you risking your content from being removed and your account limited. Your preferences seems to be quite low if you cannot notice this person disrespect the works and effort of other people by taking their pieces and attempting to claim them as their own by just doing some messy lines on top of them and washing down the original artwork.
Anyway, anyone with two fingers and just a tiny bit of artistic integrity will know how badly these fraudulent sub-derivates are, so sorry you were scammed when there are actual artists who have honest works instead of whatever these delulu individuals are trying to sell
Like, you're not even trying (more like you can't) try to disguise it
PFFFFFFFFFFFFFFFFF HHAHAHAHAHAHAHAHAHAHAHAHAHA Yeah, I totally bet I will benefit from your 3 followers that look like bots from a recently made account, suuurely.