Android Question Using WiFi AND Ethernet wire with MQTT ??

With my Tronsmart Drago box I can connect to a wired network and a WiFi network at the same time. Using MQTT the server (broker) designation is 127.0.0.1 and seems to work sending and receiving signals from WiFi AND through the Ethernet wire from different sources (a tablet WiFi and a cable networked Tronsmart box).

For the clients I specify the ip from the Ethernet OR the ip from the WiFi depending on which one I use.

• -> Are there any issues doing this?
• -> What about the off chance that two devices could have the same ip, one on the WiFi and one on the Ethernet? Would that matter?

Both networks are local closed with no internet access (10.10.10.#). I need the wired network for speed and the WiFi for the tablet connection.

Oops... I just discovered the tablet doesn't work when both WiFi and Ethernet are active. Is there a work around? Does the 127.0.0.1 default to Ethernet connections when available or something?