I use this plugin–it pulls images right from the API, which is what you’re supposed to do, I’m pretty sure:
AMZIMAGE
Most tend to gamble, here. I will say the situation I referenced in another thread where a site got the warning about unclear linking and removing PrettyLinks fixed it?
That same site had use images saved from amazon: product pages and got through the review fine. It seems like a CYA thing that Amazon doesn’t care much about unless/until a seller complains.
That said the AAWP plugin will let you use data fields as well – so you can use it to drop in just an image and be TOS compliant: https://getaawp.com/blog/create-comparison-tables-using-data-fields/