Not sure what would be considered premium, but Joplin supports KaTeX. The surprising thing about Joplin was just how much I would really love the Joplin Web Clipper browser extension. I can clip screenshots and web pages and they insert right into Joplin.
Beyond that, I use Syncthing (highly recommend if you're on Android) and I sync my Joplin notes between my PC, laptop, and Android. It works flawlessly.
I don't use Joplin because it botches my Latex, and I don't really use fancy Latex. Same with Obsidian and Zettlr. I keep going back to VSC but I'd like to see what a truly first-class technical notes experience would look like.
Beyond that, I use Syncthing (highly recommend if you're on Android) and I sync my Joplin notes between my PC, laptop, and Android. It works flawlessly.