Approach is the most unpredictable frequency you can open. Conflicts will come up.
There’s two aircraft both converging onto one point, each will reach that point in 2 minutes. 2 minutes is not a whole lot of time but it’s enough time to fix the issue. Should your objective be to, A, create vertical separation, or B, create horizontal separation.
Horizontal is the way to go. You can assign an altitude to ensure you get the required vertical separation, but the most effective path would be to create spacing.
One simple heading change of 10 to 30 degrees will do the job. If one of the two aircraft is slower performance, you’re in business. They get to go behind the faster performance aircraft. If that’s not the case, just choose at random, vector to give yourself some space, then lock in the spacing with a speed command.