@sgarciav The topology seems fine and it shoud work as expected - Deco AX3000 should be configured in AP mode to avoid double NAT in your LAN - details.

@Andre78 You can try using Method 2 from this guide for individual Deco FW update.

@eloBROWN According to this list both TP-Link routers should support Easymesh with an ethernet backhaul. But I doubt that you can use the Starlink gateway as part of that mesh - check this story....

Updating firmware to the latest release should resolve the issue described by the OP - TL-WA850RE(EU)_V7_1.0.13 Build 231115 - here. You can see more details for this particular issue in this thread....

@BobMccue1 A router integrated Speedtest is being executed from the router itself, not from the device (laptop) that you're initiating the test.

@TWillus TL-SG108 is simple 8-port unmanaged switch - it's plug and play device: Check your cabling - use a different cable or a different port on the switch.