IANAA but it seems to me that you are trying to do something in one set of books that just isn't normally done.
AIUI when I set up my books (and still use this) a set of books was designated in one currency with
all transactions in any other currency being done in the 'home' currency. (And yes I do at least
some work in other currencies. Even large companies - - - ie multi-national ones do similar.
Work is done in one currency and then when a report is pulled (closing at say 20240115 for arguments
sake) all the ledgers are closed in the main ledger which is in one currency and all the other currencies
are adjusted into that one currency.
Is not that you can't have more than one currency in a set of books but then what you have is
currency related 'messy'. So - - - in a microcosm you get to do what that multinational company
does - - - use different account numbers for similar functions in each of the different currencies.
Ja - - - its a pain - - - but your trying to stuff a dodecahedron into a sphere and wondering why the
balloon is popping - - - but the ballon was never designed to hold the dodecahedron.
In my books in account '1000' which is
Cash
bank
drafts, bank notes, checks, coins, currency, money orders, postal
notes and post-dated checks
I have different account numbers (yes I use more than 4 digits and the newer system which uses 5 digits
and is quite new I haven't adjusted to yet (GIFI courtesy of your tax bureaucracy) for each of the cash
items. I do this so I can pull up the asset values in each currency BUT my books are still done in ONE
currency.
This kind of thing is NOT going to make your books easier but if you get audited it will make them
easier to follow by whomever is doing that (which will likely make things easier for you at that point!!).
HTH