RMerlin has addressed this question a number of times in the past when it's been asked.@RMerlin Will we ever get the guest network pro VLAN features in a future release? it seems ro be in Asus firmware, not sure if i’m missing it in the merlin release.
https://www.snbforums.com/threads/a...ilable-for-the-rt-ax88u_pro.85404/post-847690
https://www.snbforums.com/threads/outlook-for-3-0-0-6-and-3-0-0-4.85663/post-851192
https://www.snbforums.com/threads/asuswrt-merlin-3004-388-4-is-now-available.86428/post-859935
Its important to note that the Guest Network Pro features in the Asus release (non Beta) firmware are currently only supported on a few Asus routers. There are other AX series routers that are supposed to support it, their 3.0.0.6 firmware is still in Beta.