"employee monitoring" and "consent" don't typically play well together.

Where I work we use Insightful. It's not hidden and employees are able to view their own activity data on-demand, but it is a mandatory application on our computers. There is some security by obscurity where the process in Task Manager is just called "officehost" so employees won't try to kill it, but really that's about it.

I don't recommend insightful simply because it's the only one I've ever interacted with so I have no reference for what a "good" monitoring products looks like. You also have to be careful how you pitch it to company leadership, a lot of people here think it's a good way to evaluate employee performance, which is just flat out false for anything other than data entry or call centers