CLI has currently feature to do this (not yet available in settings UI)
docker exec -ti softagram python3 ui/cli/softagramservice.py update_project_settings --project-id PROJECT_ID -s "impact.visualization.excluded_elem_name_patterns=pattern1,pattern2"
Example: excluding External and test
docker exec -ti softagram python3 ui/cli/softagramservice.py update_project_settings --project-id PROJECT_ID -s "impact.visualization.excluded_elem_name_patterns=External,test"
Replace PROJECT_ID with you project ID, that is visible for you in Softagram web UI URLs.
Pattern is based on Java regular expression syntax.
Note: If you want to do more complete exclusion, follow this instruction to exclude the element from the model (which causes larger consequences)
http://help.softagram.com/en/articles/3223838-excluding-element-paths-from-analysis-model
Note 2: Comma is not supported in the pattern.