Freelancers in Portugal invoicing UK clients. How to invoice and get paid?

Hi everyone! I live in Madeira and I am looking for any freelancers in Portugal who have customers in the UK? I would appreciate advice on how to invoice a UK customer… Can they receive an invoice in GBP, is this option available when entering a Recibo Verde? I assume I need the money to go into a Portuguese bank account so do I use something like Revolut where they can pay in GBP and I then transfer it? If it is relevant, I would be under the VAT threshold. Thank you to anyone who can help.