The hotel charged me in the local currency (BYN). Hence, its not the known DCC fraud.

What the hotel did was to convert the total amount in the booking confirmation (USD) to the local currency (BYN) at their unfavourable exchange rate. There is no chance for me to combat that DCC attempt.

What I could do - of course - is to request a chargeback. The booking confirmation states a USD amount and I only authorized to charge my card with that USD amount.