Yes. The law changes only for "divorces executed or modified after 2018".
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If a pre-2019 divorce is not modified, the old rules apply: the payer can deduct payments and the recipient must pay tax on them."
https://www.kiplinger.com/article/taxes/T055-C005-S001-under-the-new-tax-law-is-my-alimony-tax-free....
