There is no need to worry about key import / export. It’s all done automatically by AxCrypt via our key distribution server. All you need to do and know is the recipient(s) email-addresses (only used to identify the recipient account, not to actually email any data).
The key sharing function embeds the shared key into the file. The file must thus first be key shared with the recipient, then sent or file shared. Please note that AxCrypt does not share or send the actual file. To see a quick instructional video explaining how to use key sharing, please view https://www.youtube.com/watch?v=9z3KOZD-Yks .
Please check out our video tutorials at https://www.youtube.com/channel/UCoSoXBjq6iCG5232fHoWStA and our other documentation at https://www.axcrypt.net/documentation/get-started/ to get started with AxCrypt.