Google Search Console, in the old version, has a feature for international targeting. It lets you communicate to Google that your site is more relevant in a specific region. Gary Illyes from Google said on Reddit that this is a strong hint that "may help a little in that particular region, but won't affect your site in other regions."
He said "all you do with that doing is to very strongly hint us that your content is more relevant to users in the region you've set."
In short, if you set this, it should not negatively impact how well your site does in other regions but it may slightly improve of you do in the region you selected.
I would avoid using it if you do not want to target a specific region.
This isn't news, Google said this numerous times before but this is a good reminder.
Forum discussion at Reddit.
