Inheritence / will / trust - tax impact for non citizen wife and myself (us citizenship)

So of course this should go through a lawyer / accountant, but does anyone have a high level info for a non citizen wife in the future who may receive my assets when I (us citizen, no children) pass away? We will likely move abroad and she has a green card now, but over time will likely not renew it. We may adopt in the future.

I have a 401k, taxable brokerage, ira ... and is there any particular favored strategy to minimize any tax impact?

Such as put it in a trust and her have control / beneficiary or just do a will, but could there be significant tax impact? For example as moving assets into a trust while living or just leave her as beneficiaries in my assets? or upon death? With growth over time it could be 1 to 3 million over time (or 10 cents).