Amazon Pay for Multiple Currencies

I’m based in the UK (so my default currency is GBP) however a large majority of my business is conducted either in the US or globally, hence making USD the preferred, primary currency.

Additionally (having read the article on Amazon Pay multi-currency) it’s stated that:

No, Amazon Payments automatically convert the amount per transaction and will disburse all funds to you in your ledger currency.

And that:

To integrate Amazon Pay in multiple online stores, you need to register separate Amazon Payments merchant accounts for all your relevant shop URLs.

Is it possible to add multiple accounts within the main root account (located here) as i really don’t want to be at the mercy of Amazons auto convert feature which is no doubt influenced by global currency exchange rates and other factors.

The ideal would be sending funds from different currencies to different bank account details however this isn’t seemingly possible.

What are the options and best approach for achieving this?