Mataroa supports markdown, with images (and you can store your images on Mataroa servers), and syntax highlighted code blocks (which is something they don't openly say). I normally don't use formulae in my blog posts, so I don't know that part.

In every case, Mataroa has a free tier, so you can always try before you buy. If you want to see, my blog is at https://blog.bayindirh.io.