Hi, there. I want to know if it is ok to upload PNG files created from images I already have in my portfolio. Thanks.
Probably not. You can try uploading one, to check what happens. When they get refused for similarity you will need first to delete the accepted one. If not, you need to delete the old one after acceptance. If you delete and then upload, the picture may get a refusal and there is no guarantee that it passes. For bestsellers this is a risk I wouldn't take.