The stackry thing has been known for a while. Even to countries where kava is legal they are squeamish to ship.
You have to declare it as something else and hope they don't check it. I have options when I package it that seem to work well. I have never had a shipment to a European country seized other than a few that were going to Germany recently and I'm guessing once my packaging was spotted they are just wise to me now. I no longer ship to Germany from the UK but I do from my partner in Ireland.
@The Academic there is a very nice Fijian Waka available for shipping from Ireland now.