Since 9 months now Maxmind is not providing the CSV sources for their legacy database format, but only for their new GeoLite2 database. That is legitimate in my opinion, because the API is quite old and software projects should move to the new format, but mostly all (IMHO) important software projects still only support the old API.. :-(

So I have decided to spend again some more work in my geoip and geoip-database packages and I can say, that I will upload after the Buster release a new geoip source package, which also provides the converter I took from here:
https://github.com/mschmitt/GeoLite2xtables/

Using this converter (and some more magic etc) I am now able to build the country v4+v6 legacy edition by using the GeoLite2 CSV database source :-)

So testing will be welcome and if everything is fine buster and stretch will get backports from this work in the future.

But I had to drop now the geoip-database-extra package, which includes also the AS and City (v4) database. I didn’t find a way to convert the sources and IMO they are not so important.