DisplayLink is the only way to stop my MacBook from overheating when working with 2 external monitors
The key thing is to not use it in clamshell mode.
Also DisplayLink wouldn't really help much with running cooler, since its drawing a virtual frame buffer using your existing graphics card anyway, although I don't know if macOS would recognize it and switch to the discrete graphics when in use vs continuing to use the iGPU.
As for running cooler it really did change for me after buying DisplayLink docking station - before I would hear the fan noise constantly, now the laptop just stays quiet.