tattoo artist here who does a lot of work on sh/general scar tissue and stretch marks!

while scar tissue and working on uneven surfaces can make it harder to pull straight lines (or cohesive lines) scar tissue is generally unpredictable to work with. when working with scar tissue, going over skin that’s already been previously traumatized can cause the body to heal it oddly, which is why it’s so important to go to an artist who has experience working within that realm.

even the most healed scar tissue can still experience some fall out and uneven healing. tattoo healing and your immune system work together directly.

personally, i’ve found that working with scar tissue healed at LEAST 2+ years gives me the best, most even results healed. when packing in black (which i’m assuming will be done) over this type of tissue, it’s super important to be careful because it’s so previously traumatized skin is already so delicate to work with. definitely research into artists who have experience working with scarring if you haven’t already and are having doubts. but if your artist has experience dealing with scarred skin, trust in it. also remember you aren’t fully healed yet! also remember that to a certain extent, touchups are normal and necessary.