I understand that the Qualified Business Income deduction, introduced into law by the Tax Cuts and Job Act of 2017, is applicable at the federal level as a 20% deduction of qualified business income below threshold taxable income levels (which are stated in the first link). I am assuming that this same deduction is not applicable at the state level (however I could not find any references which categorically state this deduction is only applicable at the federal level).
Interestingly, the Tax Cuts and Jobs Act also reformed 529 plans in several key ways. For example, the legislation allows 529 plans to be used to pay for K-12 (i.e., non-higher education) tuition, which was previously NOT the case (previously only higher education expenses were allowed; see this link). In an interesting development (relevant to this question), the Nebraska state treasurer planned to ask the state legislature to introduce a bill which will align Nebraska law with federal law.
Keeping the above facts in mind, do any states have plans to introduce legislation which would enable a deduction similar to QBI, which was enabled by federal legislation?