Thank you for asking this question in the support community. There should be no configuration changes that will need to be made on the ADTRAN unit, because the configuration changes you mentioned will need to be performed on the RADIUS server. The document Configuring Microsoft IAS for RADIUS Authentication with AOS will help you setup the RADIUS server for EAP.
For additional reference the RADIUS Authentication for VPN Clients in AOS can be used to force the remote VPN clients to authenticate (which is sounds like you already have setup).
Please, do not hesitate to reply to this post with any additional information or questions. I will be happy to help in any way I can.
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