ProConnect Tax does not have the function for splitting MFJ returns.  It has to be done manually and it's a very tedious process but it can be done with some patience.  You'll need to judge for yourself whether it's worth the time and effort, depending on how simple or complex the return is.

See the post in this link for detailed instructions.  Before you "split" the return, make sure you check the MFJ/MFS comparison that you are happy with allocation and make any necessary adjustments.

https://proconnect.intuit.com/community/proconnect-tax-discussions/discussion/re-how-to-create-the-c...