I've been working on the same thing for my ReMarkable, but I get it uploaded as a newspaper doc every morning since you can't install apps on it. Overall it's been working reasonably well!

I really like the idea of reading blogs on my Kindle, so I built https://inkfeed.xyz

It's a web-based RSS reader optimized for e-ink devices (especially Kindles) that allows you to read blogs online via the Kindle browser, and download the blogs (directly on your Kindle or email it to your Kindle email).

I only tried it on my Kindle, can you try it on your ReMarkable and give me feedback?