Lumin U1 Mini - how to set up Network *without* Ethernet cables?

Thank you so much for all the helpful posts. Love this community even if I've been more an observer for a few years. 

Lumin U1 is ultimately not for me. My honest "review" if I am qualified to do that.

First the basic lack of features. 

1. Ethernet-only was a disappointment and should be mentioned more prominently in their brochureware. I tried it with Eero 6 Pro and the speed etc is fine, but even more cable spaghetti everywhere needs to be called out.
2. iPhone app is horrid. Like, really horrid. iPad-only is a stupid decision. Not everyone will lug an iPad around their home at all times. 
3. Their manuals need help too, as does their support. 

Most importantly the sound quality. My comparison is with Lindemann Limetree Bridge II that this was meant to replace. The Bridge is a tiny German made device, which unassumingly produces stellar sound -- and I thought their app was 'basic' until I saw this Lumin rubbish. The Lumin SQ is not all as stellar as raving fanboys make it out. What were they listening to before? Coming from Bridge II there's absolutely no sonic difference. 

My chain: 
Streamer (Bridge II or Lumin U1 Mini) --> RME DAC --> Dynaudio powered speakers so amp is built in  

When I had gotten Bridge II from Hifishark I was moving from Node 2i. It was a huge and audible upgrade. Node has horrid networking issues even in its version 3 (which is just called Node) and the sound was stupid, worse than my Mac Mini before. Bridge II brought joy. 

I thought I was 'upgrading' from Bridge II to the raved-about Lumin. Not at all. The streamer's job is to unintrusively pass high end signals to my DAC. The RME is a joyful piece of kit (I've also tried Denafrips Aries II and all the foaming adulation is similarly unclear to me; Aries II was an improvement over Modius for sure, but RME is perfect for me--transparent, lovely sound stage, no coloration added to make it "analog" and all that pablum) and I think the biggest difference comes from speakers anyway. 

Net net: U1 sent back. Pointlessly large piece of kit when we have options like Limetree Bridge. 

@ozzy62  great Lumin U1 works for you. I don't walk all over, but it's handy as one is often on phone and toggling quickly to music is helpful. No need to pick up another device. I suspect Bridge II would be a sufficient enough upgrade for you from Node as it was for me, and it's a tiny physical profile which is a marvel of German manufacturing...but let's enjoy what we have.

I'm grateful for all the informative posts here! 

I did try Lumin Ethernet-wired (no other way) with Eero 6 Pro Wifi-6 mesh network router. Connected to my RME by Optical digital cable. Used via Tidal Connect. I will ONLY ever use these streamers through Spotify and Tidal themselves, never their own app. (The own app is used for other settings like firmware upgrade or upsampling etc.)

I also play Limetree Bridge II with wired, but it also works flawlessly via wifi only.

Sound quality on both options was the same, running via RME to my Dynaudio speakers. But Limetree is smaller, upgrades are totally automated via web one click inside app, and optionally works completely wirelessly.

FYI - Tidal is always 44 kHz, 16 bit, with usually 1411 kbps as I have a 1 GIG wifi connection in a big city. No need for upsampling etc, although Bridge II also does upsampling with a hardware switch. I've never needed it. Sound is great without doing all this tinkering. 

Limetree Bridge II it is for me. Lumin U1 I'm sure is nice I’m sure for people who don’t mind a large clunky gadget and twice the price for the same SQ.

OK so I use coaxial SPDIF cable into RME (from my Limetree Bridge). This gives me 192khz in 24bit. Great sound, in a small package. 

Thanks to all the helpful responses. Lumin probably for another day.