No, Luminair does not support connecting to USB to DMX adaptors. Per their support site:
Will Luminair work with USB to DMX interfaces?
Created On: October 08, 2019 15:19
Luminair is not directly compatible with USB to DMX interfaces, as it isn't possible to communicate with these devices due to lack of drivers on iOS.
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The least expensive unit I've found that works is the Chauvet DMX-AN2. It's about $170 new. Can be powered via POE which is awesome.
The only sucky thing is you cannot in any way shape or form configure the stupid unit from an iOS device. It's not compatible with Safari. It took me a YEAR of swearing at it to finally figure out that you had to use Firefox on the computer in order to get into the configuration and make it work. Once I did that, it works like a champ.