@Renard In our conversation my first objective is to create network diagram for your place: what is connected to where. Then, I will need to figure how Deco mesh fits in this picture, I still have...

@stavrov Have these powerline adapters established connection to each other? If they have status lights, you can check that easily. Usually TP-Link powerline adapters are compatible with Deco mesh,...

@stavrov I would suggest you test these Tp-link adapters with Deco first. Unplug security camera and plug Deco. If Deco do work with these adapters and WiFi speed is acceptable, just get inexpensive...

@itm60 Seamless roaming between access points when moving around the house Any WiFi mesh should offer that. It is the principal difference between WiFi mesh and bunch of independent WiFi Access...

@stavrov Have you bought powerline adapters already? If not, TP-Link has adapters with two Ethernet ports, you could try those: "TP-Link AV2000 Powerline Adapter (TL-PA9020P KIT) - 2 Gigabit Ports."

@stavrov I like your plan with powerline adapters, so I'll wait till you put them in place and see the result, before discussing other options. If 2nd floor Deco can use powerline adapter to...