UPDATE: www.katiknitt.com/blog/2022/4/25/marker-texture-now-on-ko-fi
I released my Copic Marker Texture on Gumroad for free and as public domain [CC0]. https://gumroad.com/l/markertexture
I searched for textures like this a long time and couldn't find anything except for one texture that I used for a while that wasn't *explicitly* public domain. So I finally caved, made one myself and now you can just download this one as well