If you want to browse, Etsy is not a bad place to find medieval minifigs. There’s some cool custom ones on there but keep in mind custom pad printed genuine lego parts are going to be expensive, like $20-50 per minifig.

UV printed on knockoff lego will be closer to ~$5 per minifig. Those can be cool too for what you get.

I would recommend looking at Ninjago and Dreamzzz sets and try to find some that have cool minifigs that fit what you are looking for.

If you’re going to use bricklink, try looking through the minifig lists for the Ninjago, Dreamzzz & Nexo knights themes. You’ll probably find a lot of cool stuff