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).
And it does support fetching the full article using Mozilla's readability package!
Please try it and let me know what you think!
Have you tested it with Kobo devices?
No, I only have a Kindle, but if it's compatible with the Kindle browser then it may be compatible with Kobo as well.
If you have a Kobo device can you try it please?