People will try anything. I’ve even seen interconnects made of carbon dust (like spark plug wires) with very high resistance.
But I feel I should point out that any copper/silver alloy will always have a higher resistance than either pure copper or pure silver. (that is why we look for very pure copper). Sterling silver conductivity is generally about 5% below copper. (Pure silver is 7% above copper).
All that said, Mundorf markets a Cu/Ag/Au allow wire which they claim they have "experimentally" determined to be superior for audio use. I put "experimentally" in quotes because I believe the results were not measured, but judged. I have used this wire in amps and interconnects and was happy with it. However, I didn’t make identical wiring from OCC or Silver to compare.
Jerry