I just read a forum post on a diver watch forum where someone's (automatic) watch was held back by DHL because they thought the watch was a quartz watch, and had a lithium battery in it.
https://www.ups.com/content/us/en/resources/ship/packaging/guidelines/batteries.html
Been there, done that. But not online, I recently started taking watchmaking classes. Maybe this hobby ends up in a career change. But for now I have so much to learn.