Yes! We already have cross-play and cross-progression implemented and working on the current platforms (PC, PS5, Xbox SXS, and Switch).
While cross-play is always on and it doesn't require any action on your part, cross-progression is treated as an option, and as such must be activated from the Settings menu. You do not have to enable cross-progression if, for whatever reason, you would like to keep your accounts and their progress unlinked.
You can have as many secondary platforms as platforms exist, and the progress will be replicated in all of them once they’re linked. However, please keep in mind you cannot link two platforms of the same kind, for example if you have a Nintendo Switch you won't be able to link it to another Switch.
If you decide to unlink a secondary accounts, you can do so, but please be advised that the progress in your secondary account will be returned to an empty state, the same way it was after reset, with no character created on it. This is done to prevent exploits and mischief, and to encourage legitimate use of the cross-progression feature.