I have an TL-SG3428MP Switch and added two RJ-45 SFP Modules. 
 

So first the question is it possible to use LAG with SFP-Modules on TL-SG3428MP?

In Omada Controller V6 Webinterface it is not possible to setup LAG for those ports. Only if you first select an other port which is not SFP. In iOS App it is possible to setup LAG for SFP Modules. 
 

So there is an BUG, in App (API) or Webinterface from Controller. But what is physical possible with this setup?