Lightning to Ethernet Adapters

Some time ago I bought a fairly cheap Lightning to Ethernet Adapter. Minimally I thought it would be helpful for validating the Ethernet connectivity of downstream devices from my iPhone.  In other words using a cellular/mobile connection on my iPhone I wanted to use this new Ethernet adapter to connect an Ethernet connected device like a PC, smart TV, internet radio, etc.  I understand that using the iPhone's personal hotspot Wi-Fi I could make these connections but instead I wanted to use plain old wired Ethernet from my iPhone to do this.  Yes, I know I can do the Ethernet connections from other devices instead of my iPhone.

After testing my new adapter I found it only worked when connecting my iPhone to a "upstream" / "non-client" device like a router, but would not connect to any client devices.  The Ethernet adapter itself is expecting to be a "client" device similar to a PC, smart TV, internet radio, etc., NOT a device which DRIVES such client devices.  I don't know the correct internet terminology for explaining the functionality of this adapter but to prevent confusion I've grouped the following terms into two: firstly-[Upstream device, non-client device, master device] and secondly-[Downstream device, client device, slave device].  I know this terminology gets complicated when connecting pier to pier devices and upstream devices like servers but being a simple user with a router, "upstream" from me is simply "in the direction" of the telephone exchange or cell/mobile tower.  Also, I know that data traffic goes in both direction but I'm referring to capabilities of "devices" not to the direction of any specific data traffic. 

The device I bought is still useful but my question is this.  Besides correcting my internet terminology, does an adapter exist that allows me to connect my iPhone via a lightning connection to a downstream device using wired Ethernet in the same way that a personal hotspot via Wi-Fi does?  To make it perfectly simple, the Wi-Fi on only my internet radio is terrible [I believe faulty] but works perfectly when using wired Ethernet - does an adapter exist that I can send wired Ethernet from my iPhone?