bool QueryActivitiesForUsers ( const [FUniqueNetId](API\Runtime\CoreOnline\Online\FUniqueNetId) & LocalUserId, const [TArray](API\Runtime\Core\Containers\TArray)< FUniqueNetIdRef > & UserAccounts, [TOptional](API\Runtime\Core\IO\TOptional)< int32 > MaxUserActivitiesReturned, const [FOnQueryUserActivitiesComplete](API\Plugins\OnlineSubsystem\Interfaces\FOnQueryUserActivitiesComplete) & CompletionDelegate )