Last Epoch supports Steam Cloud when installed and played through Steam.
This allows your character's save data to be backed up online. Each time the game closes, your save data will be uploaded, and the latest copy of your save data will be downloaded before the game starts. Save data can be used across different operating systems.
Your save data must be converted before it can be uploaded to the Steam Cloud. This is done on a per-character basis, requiring you to enter the game with each character. After characters have been converted the Steam Cloud copy will always be used.