I would like to second the need for separating region and language settings with my specific use case.
As a Software Engineer who's native tongue is German, in my professional life I mostly use English. When I use Kagi for work related searches (e.g. technical documentation, SaaS product pages etc.), Kagi sends me to the German language versions of those sites, because my Kagi setting is "Switzerland (CH - de)".
I would prefer the English versions, because they are more familiar to me and usually of higher quality.
Examples of first results:
https://kagi.com/search?q=aws+s3 -> https://aws.amazon.com/de/s3/
https://kagi.com/search?q=azure+compute -> https://learn.microsoft.com/de-de/azure/architecture/guide/technology-choices/compute-decision-tree
I haven't set the region to "International", because I do prefer the regional slant to Switzerland, but not the language slant to German. (Especially for my private searches, which happen on the same machine.) These types of searches are so frequent for me, that it is too annoying to always switch to "International" just for that instance.
On Google, my settings are:
Results language filter: English, German
Results region: Switzerland
This results in good regional results, mostly in English. For the rare occasion that a local Swiss site has an English version, that is usually the one in my Google search results. I would prefer the German version, but am ok with this compromise because of my settings.
My machine, browser and Accept-Language are set to en-US.
A similar use case is the one of expats living in a foreign country. They would probably prefer English results but still with a regional skew.