UK specific Exchange Rate for Tax Base and Amount

How can we, in SAP S/4 HANA Cloud, implement the legal requirement for the UK where the tax amount and base need to make use of a UK specific Exchange Rate and this exchange rate needs to be printed on the invoice?

We have created a new Exchange Rate Type and we have applied that Exchange Rate Type to the Business Partner master data in the role Customer for the sales organization of UK.

We see that the Exchange Rate of that specific Exchange Rate Type is applied to the sales document when the sales document is not in GBP (it is e.g. in EUR). The tax base and tax amount of TTX1 are NOT calculated with that specific Exchange Rate Type, but these are calculated based on Exchange Rate Type M.

Is this UK specific legal requirement supported in SAP S/4 HANA Cloud? And if so, how should we adjust configuration/master data? Is there a Best Practice for this or existing documentation available?