I just stumbled upon a Dev Wiki script called ApesterIntegrator. It was archived in favor of apester tag... which I honestly had no idea even exists until now. I don't know how that tag is supposed to be used, but it doesn't look to be available on UCP based on Special:Version.
Due to being archived, the script hasn't be updated since years; but it still does seem to work well (on UCP, too) and I'd say the Apester polls look quite pleasant. So well, maybe you can give it a try?
Edit: Oh, and also keep in mind that custom JS doesn't work on mobile. Hence, any polls that are added using JS won't appear on mobile skin at all. It's recommendable to stick with content approaches that're portable. Alternatively, you can just add links to Discussions polls on the pages. But of course, it's up to you! :)