I think it's a great idea although I'd want to keep most of my financial assets, especially property, in the more climate resilient north and still continue to accumulate enough to move back north if or when it became necessary.
UK and Portugal. The COL in Portugal is roughly 40% lower than the UK, and has great weather, vibrant Latin culture, little crime, and is generally great with a northern European income.
But I'm concerned about long term water shortages and wild fires. This year water levels in reservoirs have dropped so low that you can walk the streets of long submerged villages: See:
I tried selling my Spouse on the idea of going to Delaware. On the border of Maryland. Sparse population there. +1 if we could grow most of our own food. Some spots are known to be food deserts. Plenty of spots to go fishing. Even better if my job is truly truly remote...
Delaware has no no state or local sales tax. Cheap housing as well at least from what I saw passing through (well at least compared to the DMV).
Would be a quiet place to live out the Anthropocene.