In case you haven’t seen them already, here’s two other great sites to visit.
A Book of Creatures (https://abookofcreatures.com/ is a wonderful collection of creatures and monsters drawn from a wide variety of folklore. Recent additions come from the Congo, the Czech Republic, and British comic books. If you are looking for new monsters, this is the place to look.
Les voyages de Deryn Naythas (https://derynnaythas.wordpress.com/) is a French gaming blog around the Spelljammer setting for AD&D. The Travels of Deryn Naythas is a multiversal journey between the Crystal Spheres and the Planes of Existence. If you can’t read French, look at this one through Google Translate at https://translate.google.com/translate?hl=en&sl=fr&tl=en&u=https%3A%2F%2Fderynnaythas.wordpress.com%2F I’m not much of a fan of Spelljammer myself, but I read this one mostly for the creatures that show up. Again, a good site to mine for monsters.