I don't know how to explain this well, but let's look at my thighs as squares for a second. The front is covered in scarring, but the sides and behind are completely clean. Would I still be able to get alt phalloplasty, or would I want to opt for something else? If I get phallo I want to go for alt because my forearms are quite small.
It really depends on you.
Can you do it? Yes. I've known folks doing RFF and ALT with scarring in those regions who had successful surgeries.
Will you want to do it? That's up to you. Know that anything in the graft region is going to end up on your penis. So if you are uncomfortable with the idea of those scars ending up on your penis, I would consider another donor site. You could look into scar therapies and do that along with hair removal on the donor site.
I would personally sit down with a surgeon, show them, and ask for feedback.
Sorry I am not going to be much help to OP, but I'd be really interested in more info on this. I had assumed the RFF would be out of question for me as I have extensive self harm scares, and a major surgery scar on my forearms. I mean I doubt I'd want to go with this as a donor site anyway, but I have scares on most of the donor sites and I'd like to find out more. Thanks.
I don't have a lot more to add, but might still be important. I'm not considering phallo, but I have a lot of self harm scars. The thing that comes to my mind is: what about sensation? For myself, my forearms have quite diminished sensation because of the scars covering them. If that's how it is for you too, I think it could definitely be worth taking into consideration.