Hmm. Well it could still work to a degree hopefully. I don't use REeditor though. The only players I remember off the top of my head that have full-sleeve tattoos are Brett Lawrie, Mat Latos, Justin Sellers, Ryan Roberts. But there are plenty of players that have only one or two visible tattoos on a single arm or both arms. Even fewer players have neck tattoos, such as Prince Fielder, Carl Crawford, Hanley Ramirez.
Damn, that's some insane detail! Very cool to know. Perhaps you may be willing to create cyberfaces for baseball players with tattoos on their arms and/or their necks? The list of players to do could be very long and finding detailed reference pics of a particular player's tattoos may be impossible though.
I know he isn't included, but where did that tattooed guy come from? did you do that? its incredible!! I'm only aware that you can mod player tattoos for NBA 2K.
I am gonna offer you a weird suggestion: Use a generic cyberface as a starting point in order to create facial textures. Use the generic cyberface that has certain (facial features/hair style/skin tone/facial hair) similar to the face of the actual player you are trying to create. Then modify from that and paste the textures from this face onto a cyberface of a different player that resembles more strongly to the player you are trying to create. When trying to create a player's facial hair, find pics of that player's beard/mustache/goatee from every angle as reference, copy/paste and edit from there with Photoshop. Same goes for eyebrows, lips, nose, cheeks, chin, eyebags, forehead, hairline, and sideburns.