Hi, so the WAN setting on the Netcomm is found as seen in the image below. Its quite possible the Tenda does not support vlan tagging on its WAN and the screenshot you provided supports this. As others have said, why have you chosen Tenda, its like recommending someone to buy a Lada, if you want to improve your wireless then select a device like a UniFi.
Hi Cyril. Ah, I found it now; under WAN there appears to be no specific settings for VLAN, but mine replicates the image you posted. Possibly those extra settings are only visible on the single occasion of adding a new WAN service.
As regards the Lada. Before you knock Ladas, give them a chance. This Lada has extremely good wifi performance a quantum advantage over the Netcomm and worth the low cost of unit simply for that fact. I had hoped that it would work as a fibre to ethernet source, but not to be. Have found a later version of firmware but probably wont upgrade as its only a firmware number similar to original eg V02.03.01.59_cn vs V02.03.01.82_cn and if the firmware is even for the right box.