fwiw you can use React Email pretty easily with anything by using their @react-email/render package [0] to render your email React components to HTML (this is effectively all Resend is doing in their Node library [1])

Just FYI since I happened to be looking into this recently as well :)

[0] https://www.npmjs.com/package/@react-email/render

[1] https://github.com/resendlabs/resend-node/blob/90a7225c21db9...