Making listing changes to the same ASIN between marketplaces.

Hello!

We sell the same listing both in the UK and the USA, and we would like to change some listing attributes specifically to the US listing. We can't make the changes directly on the US marketplace as the winning contribution comes from our account in the UK. We don't use "Build International Listings (BIL)".

Can anyone advise how to make changes specifically to the US listing, considering that the winning contribution comes from the UK?

Many thanks!