The connection manager (connman) supports EAP but nobody has ever written the GUI bits to configure it; because nobody among the project staff or regular contributors has ever had access to the necessary infrastructure (and in 5-6 years EAP support has been asked-for the same number of times). If you find a normal Linux distro that also uses connman and configure it there you should be able to transfer the service config files over to LE in /storage/.cache/connman/ and have it work. If some keen and capable volunteer submits the required changes to support EAP on github we'll review and hopefully merge them. I suspect the 7th-ever enquiry for EAP (in a year or so) will see me repeat this answer though.
Hi
If you could point me to the relevant code that handle the GUI popup for password in PSK mode, I may give a look at it 
GitHub - LibreELEC/service.libreelec.settings: the LibreELEC settings addon for KODI .. all development is done against master branch
I looked into this and using current code EAP can not be easily supported. Settings add-on relies on connman to ask for username/password, but connman will probably never implement interactive connection without preexisting configuration file specifying some additional info about specific network configuration. See this connman discussion: https://connman.connman.narkive.com/jcihjs8m/cannot-connect-to-eap-ieee8021x-without-a-config-file
If I create connman config file containing required info about authentication, connman asks for password/username and it connects successfully
To support EAP there would have to be some way to configure authentication before connection and creating connman configuration files using provided info.
I think the first step is to document the additional config required in our wiki so that anyone looking to use EAP understands how it's done; what info is needed and where the files need to live. Once that's understood, we can ask people to think about how
