I asked the same thing myself when I first got into this hobby a few years back. Clowns are the reason I got saltwater fish.
Unfortunately, mixing species is practically impossible. They are very territorial and intolerant of other species of clowns. Although the False Perculas can be kept in groups and seem to do well. You need to add them all at once.
I tried to add Clarkii clowns with an established pair of Percs. All h#ll broke loose, and I had to remove the Clarkii's.
If you have a very large tank, it may be possible to mix. I have seen people with two species in 180g tanks. As long as they have their own territories and enough space between those territories.