@SB19 unless you have both a reasonably fast broadband connection and decent WiFi coverage in your home this kind of issue ishighly likely. While you do not need massive bandwidth the play online downloading updates and patches on one machine will inevitably affect a second player. You do not need a full fibre connection for multiple gaming sessions it does help but often there is little you can do about your connection speed as tgst is fixed by your line but if your connection is under 30Mb/s you will hit issues with 2 players.
The second factor is the connection between the gaming device and the hub. While WiFi is convenient it is the most common cause of latency issues. Ideally use ethernet cables for gaming but improving WiFi coverage can help,to some extent. The next issue is load on your Sky hub while the hub can easily deal with a couple of gaming sessions throw in mum and dad watching Netflix and other activities it can start to struggle especially if there is limited bandwidth on the connection as it cannot prioritise gaming traffic. You can buy third party routers with a function called QOS thst can reserve bandwidth for gaming etc
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65inch Sky Glass, 3 Sky Streaming Pucks, Sky Ultrafast + and Sky SR213(white Wifi Max hub) main Wifi from 3 TP-Link Deco M4 units in access point mode
