Comment 4 for bug 1850275

glibc locale codes are defined by a combination of language and country. There is no "English-Europe" locale and no way to specify this, it cannot be missing.

You have the option of using the en_DK locale, which uses Denmark as a proxy for "generic country where English is not spoken natively." But in general, if you are not happy with the en_GB or en_US locales, it is because of some aspect of locales /other than language/ (such as currency, numeric separator, date format, etc) and you should configure the individual locale variables according to your preference instead of expecting glibc to provide a locale that exactly matches your personal preferences rather than being based on a national standard.