So I've tried to create overhead habitat paths for guests with several species like the cheetah and nyala but they are stressed all the time. Is there some one-way glass wall to line the path with to destress the animals? Or some other way to do it?
If you create the overhead path high enough that you can have terrain under it (so that it's in effect more like going over a cave rather than just a bridge), then you could add one-way glass up there and mark it as "not a habitat barrier". May not be the look you're going for, but it is an option.
Ensure every guest who can see the animal is covered by a Do Not Disturb sign and have as much shelter for the animals as you can fit in. This helped reduce my Nyala’s stress-levels from almost permanent to occasional which helps.