Mapping the currency exchange button in v5 sambapos

Hello i have a restaurant that is accepting different currencies like won dollars and euro
The problem is that i cannot just use the built in currencies button where if i clicked the euro button it will automatically convert it to euro because my product has a fix price per nationality
and also I have different department that focuses in different currencies so

US department where dollar rate is 1:1
TOKYO department where yen uses 1:1 same with others

here even if i am in TOKYO department we are are still accepting dollars but the price of the product in that department has a fix price

in sambapos there is built in currency converter but it’s only focused on 1 currency so what i did is this


so the question is can I mapped this built in button so that if I am in another department dollar rate is still 1:1 and put it here

because if it is not and just try to convert it then it always changes every time and account will be a messed up

thank you!