Hi SEO expertises!

I am currently working with a client that initially have an English website targeting UK users but want to expand their market into four new regions (Europe, America, APAC and EMEI) keeping English as a main language. I would like to request your help here as I told the client ISO location and hreflang it will be just possible per language and they must need to localise each English region with local keywords, however I would like to double check if it will be any way (Sitemap, Hreflang) we can tell Google we are targeting per region and not per country?

Thanks a lot!