At the moment I use https://lnshort.it to produce short links as naddrs in long-form posts are massive. And I add the image to the note manually. That’s the best solution I could come up with so far. Please let me know if you find a more elegant way.
You can see an example here: nostr:note1alz0lexz6nxetrac34g0pqujh98vrp8ryj6hmggvecd8pzxvan9qg6pwm0