Who's the current Witch Queen?

[Garrett Guillotte]

Elvanna's out as of 4713 AR, having served her 100-year term.

Spoiler for Reign of Winter:

The events of Reign of Winter suggest Anastasia is the likely new canon queen, barring the PCs' intervention/screwups.

Is there anything out there that confirms who the current queen is?

[Zhangar]

Elvanna until your PCs do something about it.

[James Jacobs]

Zhangar has it right. Elvanna is the current witch queen until your group plays out Reign of Winter.

If you decide to set an adventure after 4713 AR, and haven't decided the results of Reign of Winter by either playing it out, you the GM get to decide what's going on there.

[Garrett Guillotte]

Thanks!

[Mavrickindigo]

Generally I would go with Reign of Winter's suggestion. Otherwise Baba Yaga would have a new daughter you can make up