Germany can't regain its colonies without a much stronger navy in any case. It can whine about them but it can't regain them by force.
Exactly !, the Weimar Republic or "what ever they call this right wing dictatorship" has not the resource for a Plan-Z.
alternative they gain new colonies New Swabia in Antarctica
not in term of Colony to settle, more place were raw material are mine by prisoners.
or they use there rocket technology to build a vertical empire...
on last sentence i not joking!