Hey there Enyx,
Looking over the tests, Trace Route looks normal. You can safely ignore hop ten as that is just throttling/mitigation ignoring/deprioritizing the connection test requests. The Pathping is cut off at hop 4 so nothing we can use there. The link you provided went to a post about TDR errors causing stuttering?
Client lag and connection latency are not typically related though they can feel similar.
Try doing an extended power cycle on your system. Turn off all devices including the modem. Wait 30 minutes, turn on the modem, wait 5 minutes, turn on any network devices, wait 2 minutes, turn on your computer and try the game.
In some cases there is a corrupt or misconfigured setting within the router or modem. We cannot say what that might be offhand but the easiest way to resolve these conflicts would be to factory reset the router and/or modem.
You may need to look up your specific model for the steps on how to do this and in some rare cases you may need to have this done by the ISP. Feel free to reach out to them for assistance if necessary.
You can try using a VPN. This can help determine if the issue is routing based. Please note we do not support VPN usage though we do not prohibit its use with most of our games. Some countries around the world do restrict VPN usage so you will want to research these restrictions for your country before attempting to use a VPN.
Many VPNs offer a demo or trial version of their service to allow you test without commitment.
This is not meant to be the solution, just for testing but if it solves the issue and are comfortable using the VPN, you can continue to do so.
Pingplotter: Blizzard Support - Running PingPlotter
We will want 2 tests here, both 10 minutes long. While testing and replicating the issue.
The first test using the normal connection and while experiencing any of the reported issues.
The second test using an alternate device, alternate internet connection or a vpn.
That should give us a good comparison to track down any routing related issues and we can go from there.
If that doesn’t solve the issue, then I recommend submitting a ticket with an msinfo (and the pingplotter results) attached for further investigation. (instructions for collecting that msinfo report will be on the form.)
Click your name at the top right of this page, click support, click contact support.