Can ghost mantis eat dubai roaches?

Can they eat adult roaches

No. Adult Dubia roaches are way to big for them. You can try smaller nymphs as feeders.

How big are adults

Adult dubias are too big (1 1/2-2 inches). They can handle small nymphs, but I usually stick to BBs for the ghosts unless loading a female for mating or an ooth.

Adult roaches would be too large.. They are heavy and bulky. My largest female dubia is just over 2 inches I think

You could try B. lateralis, they work just fine for my ghosts. Also, not to sound like a jerk, it's Blaptica dubia. It's easy to mess up with something like the city of Dubai.

Can b. Lateral is climb or fly

They are a pest roach, go with dubia babies or young. sorry, just my opinion.....

I use lateralis. They cannot climb smooth surfaces and are not capable of upward flight--they jump and then flutter in a downward direction.

I've tried dubia and I've found that they're really large, the nymphs move too slowly to get much of a feeding response, and that they have a rather thick exoskeleton with only the abdomen being worth eating.

lateralis are only a pest species if they escape, which is easily preventable. Even if they do escape, they need fairly warm environments to breed and mature. Make sure you keep them in a very smooth sided, tall container, and monitor feeding. Sometimes you have to be quick and willing to grab em, but I've never had a problem with that. I tend not to use B. dubia for feeders, for the reasons Ranitomeya pointed out. They do work pretty well if your mantis takes food from tongs, however.