ASUS RT-AC88U compatibility

First of all, my apologies because I’m using the English language. My Dutch language skills still sucks.

To give some context to whoever may read this, I must say I work as a software engineer and have an IT background with many years of experience, so I might have some idea of what I’m talking about.

I got a T-Mobile Thuis 1Gbps optic fiber connection on April 2nd. Mandatory for my work and nowadays virus crisis, and of course because I like to decently play online games and watch movies and stuff with decent quality.

My problem (you can skip to the ‘My question’ section)

Ethernet connection to the router seems to work fine. No interruptions, decent speed… what you can get from a 100Mbps ethernet port… because of Zyxel [facepalm].

I have many many wifi problems and nothing of what I did worked 100%. The speed is good (almost as expected), stability is kind of good, but every few minutes, there’s an interruption in the WiFi. When I’m in a call with my coworkers, or using discord, or playing games which don’t need a lot of stability, such as World of Warcraft, DOOM Eternal (no multiplayer), and so on, there’s no problem.

The problem comes with other devices (I’m not the only one using the WiFi) such as tablets, some smartphones, and when I’m playing games where you must have a decent connection (like shooters). Latency is good, but it doesn’t matter if I’m connected to the 5Ghz or the 2.4Ghz frequency bands, I get very small connection interruptions which make my online experience a hell.

I can provide, if needed, a lot of details about what I have tried: trying to use only one frequency band at the time, manually selecting the best channel for every frequency (after I did a coverage analysis), modifying settings in my wifi card and the mobile devices, buying a new wifi card, etc.

My question

I want to get rid of the crappy Zyxel router that T-Mobile gave me, and use the Asus RT-AC88U instead.

I’ve seen that the connection to the Zyxel router is done via RJ45 ethernet cable, from the media converter to its WAN port. The technician who did the installation did nothing else, just install the media converter and connect the Zyxel router to it via an ethernet cable. Even after I hard reset the router several times, that still works.

The Asus router has a RJ45 ethernet WAN port. I was wondering if I can replace the Zyxel router by the Asus one (not connecting the ASUS to one ethernet port in the Zyxel router).

I’ve read other topics in this forum and apparently some other user had a similar question. His problem was that he got the same ASUS router that I want to buy, but he had DSL connection (I almost die when I saw the pic where he connected the RJ11 phone cable to the RJ45 WAN port in the router).

I’m assuming what I want to do works, but I want to be sure first, because one doesn’t invest almost 300 euros in a wifi router every day.

Many many thanks in advance for your time, help and suggestions. And again, my apologies for using the English language.