Exchange rate for accounts receivable / provision for ex rate loss

I would like to use different exchange rate for the accounts receivable for conversion to base currency to provide for futuristic exchange rate loss etc or being cautious. How do we do that.

Is there a way to create option for entering exchange rate either way we like eg: INR to USD or USD to INR

Sorry, but this doesn’t make much sense.

If you have unpaid sales invoice for $1000 USD and bank account with $1000 USD in it, both are assets worth $1000 USD each and both would be converted to INR using the same exchange rate for reporting purposes.