How to split Minimum Tax Credit from prior year when filing status changes from Joint filing to separate filing?

Yes, you can split your Minimum Tax Credit.  To do so in TurboTax Online, while logged in to your return, 

• Click on Tax Home
• Select "Deductions and Credits"
• Scroll down to "Estimates and Other Taxes Paid" and click to expand the menu
• Scroll down to the bottom click on "Start/Revisit" next to "Other Credits"
• Scroll down to "Credit for AMT Paid in Prior Year" and click on Start
• Answer the questions and enter your minimum tax credit carry forward