Went from the US to Germany in December, stored all my gear broken down in a zip lock bag, didn't remove stickers because then they will have to test the liquid, since everybody can say its just for vaping, making them work more and if I learned one thing, never piss off airport security or/and customs lol.
The Issue they did have tho were the batteries, they even kept them saying its a risk on long flights like that. Fine for me just got new ones as I stopped in France, apparently inside Europe it wasn't problematic enough and they let me keep them in my bag as I entered the connection flight. My ego aio pen on the other hand, no issues what so ever. They just hate 18650s? Lol
So make sure you read the guidelines or call and ask if not certain.