Out of curiosity, what Firefox addons do you have in mind?
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No, add-ons have a list of applications they support coded into them, and it wouldn't make sense for a lot of them to be interchangeable. You don't need adblock in Thunderbird, you need spam filtering.
I'd definitely wanna block embedded trackers though
Thunderbird does that by default. As long as you don't enable downloading of external resources, trackers are blocked.
How does it work though, does it use tracker lists like uBlock origin does?
Trackers are basically embedded images in the email. If the image gets downloaded by your client, they can track if the email was opened. If you simply don't download images, there's no tracking.
Browsers work very different than mails :)
In Mails normally you get the content you want sent. Tracking only happens if the content is not sent, but needs to be downloaded from within the app. Then the servers can see you got the mail.
MV2 extensions should work in Thunderbird without modification. I've made a couple of simple extensions that work like a charm in both Firefox and Thunderbird, but I'm not sure if more complex extensions would have issues. The documentation says thus:
Some information listed on MDN may not apply to Thunderbird and some API methods may not be supported. Each API page should include a compatibility chart and if that includes support for Firefox, it should work in Thunderbird as well.
Some MV3 extensions will not work in Thunderbird. See this page for list of missing functionality.
Most dont work but you can download the .xpi files from within the browser using the addon "extension source viewer" and then sideload in Thunderbird by "install addon from file".