Pension payouts to my ex spouse

It depends on whether the payments can be considered as alimony or not.

The IRS provides guidelines on what is and what is not alimony in this document.

According to the Tax Cuts and Jobs Act of 2017, alimony payments will no longer be tax-deductible to the payer or includible in the income of the recipient if made under:

a) A divorce or separation agreement entered into after December 31, 2018; or

b) A divorce or separation agreement entered into on or before December 31, 2018 but modified after that date if the modified agreement specifically provides that the provisions of the Tax Cuts and Jobs Act of 2017 will apply

Alimony payments made under a divorce or separation agreement entered into on or before December 31, 2018 but paid after that date—with the exception of such payments made under a modified agreement described in b) above—will continue to be tax-deductible to the payer and includible in the income of the recipient.

If it is "not alimony", then the entire pension is taxable to you and you can't make any adjustments for what you pay your ex.

However, you can ask the family court for a QDRO, qualified domestic relations order.  This is an order from the court directing the pension payer to pay part of the pension to your ex.  Your ex would get a 1099-R for the part paid to them and your 1099-R would only show the part paid to you (starting from the date the pension payer processed the QDRO, of course.)