Do all members have EU passports?
Was a UK EMI the first to ban you? I ask as there is chance if the ban was related to fraud i.e suspect documents you provided them then your almost certainly been entered in the UK CIFAS blacklist database by them. Wise, Revoult and other UK banks etc all are
members of CIFAS and use this database to blacklist clients. You would be persona non-grata (banned) for business in UK if its the case.
You can make a request below to see if its the case.
https://www.cifas.org.uk/individuals
P.S Hopefully none of above is true and it is simply EMI's internal rules and they don't like UK LLP's of non-residents following the Scottish LLP's and money laundering scandal as they see them as high risk. In which case you need a high risk EMI.
https://www.bbc.com/news/uk-scotland-scotland-business-43935839