Limit Security Group Assignment to specific OU

If this feature is already available, I would gladly appreciate help in setting it up.

Case scenario.
in our setup, I have Clients OU that contains a number of individual OUs specific to client (example: Clients -> ClientA, ClientB, ClientC ..etc. ): Within each client OU, there are domain accounts and security groups specific to the client (Clients -> ClientA -> userA1, userA2, userA3, securityA10, securityA20..etc).

Using AD manager, I can assign one (unique) technician to each of clients OU to manage - so TechnicianA will have privileges w/n Clients->ClientA OU. That way, he can only assign users(A) to security groups A(0). There won't be a possibility to assign userA to securityB (under clientB).

My issue is when a technician needs to have access to more than one client OU. If I allow technicianA access to ClientB, he will be able to mix users/security groups between A and B clients. Is there a way to restrict that technician with access to multiple OUs can only change/update user security group w/n that user OU?