Well had to make a lot of changes on payment screen but I think I finally achieved something useful. Let me demonstrate it for now, I’ll upload it soon.
Case 1. Single Foreign Currency, Two Change Templates.
In this case additional change template configured for default cash account. This account have no currency assigned.
Exchange rate for MXN configured as 20.
We assume default currency is $.
On this sample we’ll tender 9$ give 40 MXN and $0.51 back.
I cleared transactions to review how it reflects to accounting and made a similar transaction. This time I selected MXN before entering tendered amount.
Same Transaction. This time I selected $ as whole change.
###Case 2: 3 Currencies. 3 Change templates
In this case I also configured a currency for default currency so with additional 2 foreign currencies (TL, MXN) we have 3 currencies. We also have 3 Change Templates.
To create an extreme case I’ll create $6.49 ticket, settle $10 and split change to 10 TL and remaining as MXN.
Bonus Uber Case 
Modifications I’ve made how change templates works now allows us to apply change amounts to non payment accounts. For example we can credit all or part of change amount to Customer Account.
In this case we have single foreign currency and 3 change templates. One for Default currency, one for foreign (MXN) currency and one for customer account. I’ll create two tickets to demonstrate splitting change amount or apply it as a whole.
You’ll notice Customer Credit option appears when we select a customer to ticket. For SambaCard implementation we may have additional change templates so related change buttons will appear.
I hope these features improves how you handle changes.