@Honoken TP-Link's DDNS service is running on the router and sends the WAN IP address updates periodically for your registered name - details. Same goes for the no-ip DDNS service provider.

@Red4050 When your AX4400 is connected to the switch what are its WAN (Internet) port settings: Is the switch in question a plain unmanaged switch ? In what mode your ISP modem works - modem router...

@GRMLP Device like Deco X50 (rated as AX3000) should be able to utilize an ISP speed of 1gbps via wireless.

@Vecchihwchuck In theory the aswer is yes - check this FAQ for more details on your question.

@TimsNetwork Probably the best option is to use the Network Map => Clients of your router:

@Rusty-Crudd You should probably go through this thread.