I have a 200a service for mobile home will be adding another mobile can I add another 200A load center @ power pole come out of existing panel to feed new box?

Sure, but both homes will be limited to a total capacity of the incoming 200 amp service.

That's okay everything in home will not be used. 2 water heaters 2 a/c pressure tank other outlets ,2 refrigerators basically combining 2 homes

You do realize the incoming service will not be sized properly for both homes, and the Main may be tripping frequently. What type of heat is in the two homes?

This also assumes there will be ONE 200 amp main for both.

Both have central heat and air