I don’t know if this will help you but having used/tried too many apps., I have settled successfully and happily with Apple Notes (I can type and/or handwrite my notes) and then export them as needed to DevonThink. This works perfectly for me.
Notebooks is cross-platform, Mac, iOS, and Windows.
I use it for research notes, mainly on Mac.
I’m a bit miffed that I bought it in January and would need to pay $36 if I want to upgrade to v2. I’m digging in my heels with 1.x at the moment.
Depending on what is in your notes, if it is only text, you could look at Standard Notes. It’s a secure note platform, meaning everything is encrypted. I’ve been using it for about 6 months and love it, I purchased the 5 year Extended plan, but if you are only using it for plain text, the free version is more than enough.
I did end up going back to Standard Notes for secure notes. Mainly for notes that I access on my work computer, that I didn’t want saved to the machine in plain text. Also I’m not sure whether the developer fixed my issues with Electron or if Electron has been steadily improving, but the issues I was having are no longer happening, mainly with copy and paste.
As for the editor, the Plus Editor has a limited font selection:
I only use the Advanced Markdown editor, which doesn’t have fonts, so there might be other editors with fonts as well but I’ve not found them.
Also editors are really just previews of the text, at the base it is still plain text files so if you make changes for rich rext, when you go back to the plain text editor, it will show the HTML plain text markup.