In the animated movie Batman: Hush (2019), Clark Kent and Bruce Wayne meet with each other, when Bruce comes to give an interview to Lois Lane. In this movie, does Superman know about the identity of Batman, namely that he is Bruce Wayne?
For the long answer, you may or may not know that it's part of the canon know as DC Animated Movie Universe, so everything that happened in previous films still canon to this one.
In Justice League: War (2014):
During a fight between Green Lantern/Batman vs Superman, Batman calls Superman "Clark" and in return Superman use his X-Ray vision and call him "Bruce Wayne". Batman didn't even try to hide his identity as in the previous scene he even told his secret identity to Green Lantern Hal Jordan.
Video for the same:
Yes. In this story, Batman and Superman know each other's identity.
But they don't work together. Because Batman believes that Superman is too soft on the criminals, and Superman believes that Batman is too aggressive in the way he works.
However, they do respect each other and because of that, they have an agreement that they both stay in their respective cities. That is why Bruce came to Metropolis under the guise of an interview with Lois: to honor the agreement he has with Superman, but still, be able to continue his investigation.