This guide lists the locations of the Demiguise statues by map and by Alohomora level access. Why? Because I spent a ton of time searching, backtracking, and getting frustrated that I didn't have Alohomora Level 2. Add in all the other collectibles that can be missed and I decided to minimise the pain where possible. A quick list like this may be helpful.

If you need a full guide to finding the exact locations of each statue, there are plenty of video and screenshot guides on Youtube and Steam. I can recommend PowerPyx's channel for a full video guide to Demiguise collection.