TP-Link powerline adapter causing extreme latency on primary network? Wired devices on Fios router, not connected to powerline adapter, are affected

Question

To preface, I am not a networking guy but work in IT. I'm going to bullet point the situation so it's easier to digest. Here is a little diagram I created in paint to give a visual aid.

1. I pay for Fios Gigabit Internet

2. I use the Fios Quantum Gateway router

3. I use a TP Link AV600 powerline adapter so the Firestick in my living room has access to a network. This is a separate SSID than the "primary network" as I put it in the title.

4. My desktop is directly wired to the Fios Quantum Gateway router

5. Powerline adapter is plugged in directly to the router on one end, and the other end that broadcasts the wireless signal for the TV to connect to is plugged into a different outlet on the other side of the house

6. When the powerline adapter is in use, I get extreme latency while trying to game on the wired PC connected to the Fios router

7. The powerline adapter is NOT in between the PC and the Fios router

8. I came to the conclusion that the latency on my PC resulted from powerline adapter by unplugging the powerline adapter and pinging my router (ping -t 192.168.1.1); I played a game for about 15-20 minutes and didn't have one spike over 2ms, 99% were <1ms. I then plugged the powerline adapter back in and started streaming a random Netflix show on the firestick and the latency from my desktop to the router almost immediately jumped to 300-600ms. Streaming a Netflix show from a device on the primary network does not affect latency, or at least extremely marginally.

The only thing I can think of is that the router is not routing the packets correctly which is causing a delay during that process? Would a network switch help with this, or would that not be any better than the router's switch? Would creating a VLAN for the powerline adapter traffic help? I'm probably completely off here but was the first thing I could think of. I cannot figure out why my wired connection between PC and Fios router would be so heavily affected by traffic on the powerline adapter's connection