I got a 10 years UK visa ban a few years ago. Since then I obtained a new citizenship (it is of European Union, the country belongs to Schengen treaty, and does not fall under immigration rules), so it does not require me having a visa to enter anymore. The surname has also slightly changed (mostly the spelling). Will I be able to enter the UK with my new citizenship and the new ID (yes, there are biometrics)? Is there any legal way to overcome this ban, since I’m a citizen of a new country? Thanks you for the response in advance
This answer assumes that "(European)" means that your new country of citizenship is a member of the EU or the Schengen area.
In that case, if you are entering the UK while the Immigration (European Economic Area) Regulations 2016 are in force, the ban has no effect, because the ban is effective only under the Immigration Rules, of which the Regulations are independent. (If the UK leaves the EU without a deal, however, it is expected that the Regulations will be repealed fairly quickly, in which case your ban will likely become effective once again.)