Transfer Account function allows you to carry over your player data from another device.
Transferring data will delete any player data already on a device and overwrite it with the transferred data.
Also, if you transfer your account to a different operating system (iOS or Android or Steam), Paid Lodestar Gems you own on the original operating system will not be transferred to the new operating system, but will remain on the account's original operating system.
There are two ways to Transfer Account: with Apple ID and with Google Account. For more details, please refer to the following.
FAQ:【Atelier Resleriana: Forgotten Alchemy and the Polar Night Liberator】How to Link Account
FAQ:【Atelier Resleriana】How to Transfer Account