Hello,
Yes, there is. The workflow looks like this User turned inactive => Get user info => If (Specific OU) => Suspend user.
The User turned inactive trigger will output the inactive user's primary email as a variable (you can think it as metadata), then use the Get user info action to retrieve the full profile of the user, including the OU the user is in. The profile variables will pass down the flow.
In the If action, rename the Branch 1 to specific OU or something and set condition as Organization Unit Path text is exactly /OU/SubOU/SubSubOU. Replace the /OU/SubOU/SubSubOU with your organizational setting. Please note it's case-sensitive. Then add Suspend user action after this branch. Ignore the Fallback branch. That means, if the inactive user is not in the given OU, do nothing.
You can change the condition to Organization Unit Path text starts with /OU/SubOU to also include all SubSubOUs.
Thanks.