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.