MongoDB Replication of two Primary

For our project we need to replicate two MongoDB primary databases from one site to another.

Simple Overview

Now we have the problem, that we wanna access data of Site B with a client over Site A. So we need to replicate the data from Site B to Site A cause MongoDB does not support Master-Master replication and we need to use MongoDB for other reason. There are more reason to build this architecture, but they are not necessary to explain my problem.

My plan is a cross-replication with two primary and two secondary data-sets.

Replication Plan

For reading a client needs access to on Site A Primary A and Secondary B.

Does anyone have experience with it? Is it possible to do that or does anyone have a better solution for my problem?

Thank you.