Is the MSI GeForce GTX 1660 SUPER VENTUS XS OC, 6GB GDDR6 good GPU for video editig?

The GTX 1660 Super will work just fine in Premiere Pro. In fact, it is a variant of the Adobe-recommended GTX 1660 Ti, with fewer CUDA cores but slightly higher memory speed.

That said, DDR4 system RAM is now cheap enough that there is no excuse at all whatsoever to go with anything less than 32 GB even for a 6-core/12-thread CPU-based PC.

And I would also recommend a second, larger-capacity internal SSD (which may be either a SATA or an m.2 PCI-E NVMe SSD) for your media and project files. No external HDD is anywhere near as fast as what I would recommend as a projects/media drive.

These are the exact reasons why I went AMD instead of Intel when it came time to upgrade to a newer CPU platform back in December of last year. At the time, Intel did not offer anything that was compelling enough for me to pay anywhere near its asking price for both the CPU and motherboard combined. In fact, at the price point of my current Ryzen 7 3800X, Intel offered only an 8-core/8-thread CPU (the i7-9700K) that would have been at best only about as powerful as a much cheaper Ryzen 5 3600, at a price that was $150 USD higher. And none of the cheaper CPUs that Intel offered at the time was a big enough improvement over my then-quad-core (8-thread) CPUs that I was using in my reserve PC at the time to justify paying the price for such a platform update. And had I gone with the lone mainstream-platform Intel CPU that did, I would have been forced to cut corners everywhere else in my upgrade: going with only 8 GB total of RAM and foregoing both GPU and storage upgrades (I would have been stuck with a 2016-era GTX 1060 GPU and smaller-capacity SATA SSDs instead of the RTX 2060 Super and two m.2 NVMe SSDs that are currently in my AMD main build).

Adobe does not test every card

https://community.adobe.com/t5/video-hardware/article-by-dave-helmly-on-hardware-for-running-premiere-pro-aftereffects/td-p/11369321?page=1