Optical Thunderbolt 3 cable would probably be best but you need a working Thunderbolt 3 add-in card since the optical Thunderbolt 3 cable won't support DisplayPort alt mode.I found this, but it isn’t bi-directional, nor USB-C…
CABLEDECONN Fiber 8K 4K DisplayPort1.4 Cable DP 8K HBR3 8K@60Hz 4K@144Hz High Speed 32.4Gbps Optical Fiber Slim and Flexible DP to DP Cable 10m 33ft
CABLEDECONN Fiber 8K 4K DisplayPort1.4 Cable DP 8K HBR3 8K@60Hz 4K@144Hz High Speed 32.4Gbps Optical Fiber Slim and Flexible DP to DP Cable 10m 33ftwww.amazon.ca
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