Currently bank tagging only supports same currency tagging. E.g. if the bank you’re working on is denominated in GBP, the tagging process will only reveal invoices raised in GBP.
If you’re logging GBP payments against a USD invoice you would need to first lodge the credit on account in USD from the client screen then go to each invoice and pay down using the credit.
If this is a regular thing on your accounts you could create a separate holdings account in USD pay all USD invoices to here then treat the entry on the GBP account as a transfer to the USD account.