Not sure if people will find this useful (or if someone else has already pointed this out), but I thought I’d post this anyway. I’d been hoping that there was a way of serving poured glasses of nectar to other sims like you can with the tea sets from My Wedding Stories and was a bit disappointed that there wasn’t one. But then I remembered that the interaction to serve tea is on the tea set itself, not the actual cups of tea, so I tried to see if dragging nectar glasses onto an empty tea set would allow you to use the ‘serve tea’ interaction with them.
Sure enough, it does! It looks like putting any drink onto the tea set will allow the serving option, and my sim took the glass and gave it to the other sim (who drank it).