920 stock temp???

It is normal for there to be a slight difference in temperatures over the 4 cores. However this should be only 1-2 degrees at the most while idling. Obviously under load some software will only utilise 1 or 2 cores...

Core Temp / Real Temp or even your own motherboard software will give you different readings - some use the sensors on the chip some use sensors on the mobo under the CPU socket.

Your temps are will within normal operating range so I wouldnt worry.

but keep in mind i am using the corsair h50 cooler...shouldn't it cool down a bit more?

These temps are normal as the i7-9xx runs really hot.

In addition, different software show different core temps due to their TJ Max being set to different values.

The TJ Max of EVGA app is 2 degrees higher than the core temp according to the picture attached.

BTW, your Vcore is way too high at this frequency and it should be below 1.20V.

Lower your CPU Vcore and you should get better core temps thereafter.