I have multiple identical complex states.
First, to do this, I need to show a state that is complex but with its decomposition hidden, like this:

I didn't find a way to do this with PlantUML. I am currently using the text description.
Secondly, I would like to show the exitpoint of that machine. However putting exitpoints on a state make it complex, and unreasonably large; in addition the exitpoints tend to overlap:
@startuml
[*] --> MainPhase
state MainPhase {
state "ready" as main_ready <<exitpoint>>
state "other" as main_other <<exitpoint>>
}
main_ready --> DrawPhase
DrawPhase --> AttackPhase
MainPhase : internal machine
AttackPhase : internal machine
state AttackPhase {
state "ready" as attack_ready <<exitpoint>>
state "other" as attack_other <<exitpoint>>
}
attack_ready --> [*]
state "internal machine" as _Internal {
[*] --> A
A --> B
}
@enduml

Example overlapping exitpoints in nested states:
