Prepositions with states

Lucy, 

I would have said ‘ dans le Kansas ‘ based on the 2nd and 3rd links below, which both appear consistent with traditional metropolitan French usage - the form preferred and generally taught on this site. I will continue with this usage, as my connection to French is to the ‘hexagone’.

I noted however that DeepL preferred ‘ au Kansas ‘ and further searching explains why, I think.

The official position of Québécois French is that either is correct, with ‘ au Kansas ‘ listed first.   

https://vitrinelinguistique.oqlf.gouv.qc.ca/24891/la-syntaxe/les-prepositions/preposition-devant-un-nom/les-prepositions-devant-un-nom-detat-americain#

En/Dans = in/to + regions/states/counties (French Prepositions) 

https://www.lawlessfrench.com/grammar/geographical-prepositions-regions-departments/