This is expected.
The locale that you use to create a new rule ends up being registered in the brl/rfl/dta/ etc... files that save the rules / ruleflows :
You will see:
<locale>en_US</locale>
So just importing an existing rule project in a Rule Designer that was started with a different locale won't change that.
When switching between Dutch or English, it may seems easy to just re-read the rule in an other locale (interchangeable), but this is not always true.
The sentence grammatical order may be completely different. For instance if you switch from Japanese to English.
#OperationalDecisionManager(ODM)#Support#SupportMigration