Change RDS read replica parameter group without affecting main

Hi,

is it possible to change the parameter group associated to a MySQL read replica without affecting the main rds? I've got the main rds using the default parameter group for mysql 8.0, and a read-replica with that same parameter group. I need to change some values in that parameter group but cannot afford downtime on the main. I've seen that when modifying the read replica, the aws console allows me to change the parameter group, but I wonder whether that changes is also applied to the main or not.

Thanks for the info!