A review site seems like a fun idea! It's always good to get constructive criticism when you put things out there.
Personally it would be good to reach out to the artist if you can, to see what is off limits for the author or if they have anything personally they wanted added to the review (artist comment or other links etc).
Unless you're making intentional inflationary comments or posting spoilers or tapas paid content on the review site itself, I don't think you'd get sued. Check out copyright and review guideline sites for tips. Just googling and I found these: