Short of a State's outright nullification--a precursor to secession--of an unconstitutional federal act by the judiciary, congress or the executive branch, per Printz v US (1842) and James Madison's counsel on the subject in Federalist #46, a State may simply refuse to enforce the act within its sovereign territory. This is referred to as "anti-commandeering", a perfectly legitimate remedy to federal overreach which even our renegade courts have upheld over the years. (Though I discussed this subject in my book, "A Patriot's Call to Action", it bears repeating here.)
With this doctrine in mind, Texas is introducing legislation to establish a permanent committee to review any and all edicts, laws, regulations issued by the federal government to ensure their strict comportment with the original Constitution. And if a federal act is rendered unconstitutional by the committee--and so many federal acts these days are just that--the State legislature (both houses) would vote on whether or not that particular act is constitutional and whether or not Texas will honor the act. With legislative passage and the Governor's signature, the federal act in question would not be honored or otherwise enforced in the State.
**If ALL States were to replicate this approach, federal tyranny would be drastically reduced throughout the land and a semblance of constitutional order would quickly return to this tattered republic.
NOTE: Nullification is a much more serious--but entirely legitimate--remedy as well. Invoking the 10th Amendment authority to nullify a federal act would entail a State's arresting, fining and imprisoning both State and Federal agents who attempt to enforce a federal act rendered unconstitutional by the State. Invoking the Anti-Commandeering Doctrine is a gentler way to achieving the same result, that being to render an unconstitutional federal act of no effect within a State's sovereign territory.
Nice to see Texas once again taking the lead in returning our republic to its first-principles. Would love to see other States do the same. Sadly, I fear most are too heavily bribed by the feds to resist by either method. And so it goes...