A way to set TARGET_GROUP_LIST="_all_" to automatically assign the instances target group?

In the ELB common_function.sh you could set the ELB_LIST='_all_' and that would prevent the need to hard code ELB values. Im wondering if there is a way to do this for an ALB in elb_v2/ for TARGET_GROUP_LIST.

I have different TG for dev, staging, and prod and would have to manually change the script for every region, in addition the way our setup works it auto generates a TG name so if anything needed to change we would need to modify the script again as the TG name would have changed.