So this is something that bothered me quite a long time already, whenever I play with friends on my PS4 it starts lagging even when it's just me and someone else. It happens when one of us starts crafting or opens the Inventory. And as soon as one of us leaves that menu it gets normal again.

We are playing offline, so it can't be the Internet Connection.

It happens on every possible setting.

No special textures or anything else, just default Minecraft bedrock edition.