This is caused by where the IP is registered and where it is deployed.
In the case of 23.137.249.127, maxmind says this:
country->isoCode NL - registeredCountry->isoCode US
The CIDR 23.0.0.0/8 is allocated to ARIN (American Registry for Internet Numbers) https://whois.arin.net/ui/
So for 23.137.249.127
It is owned by IncogNET LLC which owns 23.137.248.0/21 but 23.137.249.127 is deployed in NL
Company IncogNet LLC
Street 30 N Gould St, STE 4000
City Sheridan
State/Province WY
Postal Code 82801
Country US
You can find relevant threads in the tor-relays-list archive.
¹In my bug report, you can also read why ARIN IPs in particular so often have incorrect data. As always, it’s about money. The best thing is to ask the provider for geofeed data like I did with Frantech.
A few years ago, TorProject had to change its database because Maxmind changed its license and wanted money for access.
IPFire is open source and free forever. All improvements benefit the entire open source community forever.