Version 026.1 New GlobalVariable SKK_CSUseFactionRelationActors to disable adding actors from scripted factions (Institute, BOS, RailRoad) to hostile form lists.

Sample Feral hostiles only XEdit override file. Use with base version 026 or later. Yes of course you need the base mod and this needs to load after it . To create custom hostile lists refer to the add and remove hostiles article.