tf2 is a horribly optimized game from whatever reason. my only recommendations is to:
1) Check multi-core rendering (sounds stupid but might as well)
2) use dxlevel 96-99 and set everything in the TF2 Graphics settings to "high"
3) Check task manager if it's not utilizing all of your CPU's cores into TF2 (under set affinity), I had an issue where it only used 2 out of the 4 I had and that was really annoying.
3.5) While you're at it set the priority to high (not realtime)
4) Disable explosions using cfg.tf
5) Recreate a config using the mastercomfig app @ https://mastercomfig.com/ it does an AMAZING job at tweaking your game to get the most frames out of it
6) Disable or Re-enable game mode on windows 10 (some people find it helpful and some find it worse)
7) Keep all your drivers up to date! That sounds like a no brainier but updates for these come out all the time and you never know until you try.
8) TF2 might utilize your intergrated graphics rather than your dedicated graphics card. Have a go at googling how to drive tf2 to utilize your graphics card. (another way of doing that is checking your cable into the monitor is thru the card and not your motherboard)
9) Go to device manager and click display adapters, click on your gtx 2060, then go to details and choose hardware ids now copy these two
then put this on your run options
-force_vendor_id 0x"put ven id here" -force_device_id 0x"put dev id here"
it"ll look like this if you have a 620M
-force_vendor_id 0x10de -force_device_id 0x1140
got that from the reddit user SMAn991
10) Delete system32