Could one say: "vi junas kaj sanas, vi povas labori"? I reported it because I'm pretty sure it's possible, but maybe I'm missing something. Any help here is appreciated.
Yes, but I believe it's a less common form than 'estas juna kaj sana.'
One could also say «Vi estas junaj kaj sanaj,» and suggest talking to plural people.
One could, but unfortunately it is not accepted (yet!)
No, it isn't. and there's no reason, yet, that it should be.
This is still the case today (2021-08-11) that talking to plural people is not yet accepted. (I've reported it.)