I'm in CA.
Lacerte has a tool (Tools>Split Joint Return...) to split the MFJ return (that you won't file, but keep for reference) and create two separate MFS files for you. You have to do a small bit of clean up with info diagnostics and some review, but it does a pretty good job.
It splits both fed and CA. Make sure on Screen 3 that you are applying community property rules before you split it.
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