Yes, there are USB 3.1 type-c adapters compatible with 5Gb Ethernet.
Yes, there are USB 3.1 type-c adapters compatible with 5Gb Ethernet.
I purchased the Startech branded adapter featuring a regular USB 3.0 A port at the end because it was more affordable compared to the Qnap model. The internal chipset remains the same.
Looks accurate. My performance reaches its peak near 444MB when the client and NAS/Server MTU are configured at 6000. In fact, using 9000 tends to make things slower.