Image in Library mode is colorized with warm-sephia tone. Preview on second monitor it's also warmer, like in Library mode. In Develop mode image looks right.
It happens on both displays I have.
First image - right, second - warmed by Lightroom
Export looks correct, like in Develop mode.
The thread that Akash linked to is mostly about differences in noise.
I suggest that you look here instead: Lightroom 6 picture problems
You probably have a defective monitor profile.