does GV-USB2 work on nintendo switch? also does it come with everything you need to set it up or do you need to buy extra accesories? could someone link me to a place to buy one?

The GV-USB2: http://a.co/d/1A4Y4B5 doesn't directly work with the Switch HDMI. You're going to need an HDMI to RCA adapter like this one: http://a.co/d/3hExKG0

When you plug the GV-USB2 into your computer you should be able to use it as a video source in OBS.

if i bought this, would it be all i need? https://www.amazon.com/USB-Video-Capture-Device-DriverGenius/dp/B07448TTTH/ref=mp_s_a_1_11?ie=UTF8&qid=1536437257&sr=8-11&pi=AC_SX236_SY340_QL65&keywords=elgato+hd60s&dpPl=1&dpID=41mHRnTLGpL&ref=plSrch

to record on switch

No. You also need an HDMI to RCA adapter like this: http://a.co/d/3hExKG0

that one says hdmi to rca instead of rca to hdmi...is that the same thing?

No, they are different. If you want to connect your switch to the capture card, you're going to need an HDMI to RCA. Otherwise it won't work.

Just sell your switch for a good Capture Card Kappa

Then the point would be useless now