In RC/Migrator an ALTER strategy can be used to add Include columns to an existing index.
See the attached .pdf with screen flow to add an Include Index column to an index using an ALTER strategy.
For more detail see the RC/Migrator Guide: Unique Index INCLUDE column support
The above documentation mentions the use of profiles, below is some additional information.
When analyzing strategies in RC/Migrator, an existing Analysis Profile can be used by entering the profile name and creator on the analysis screen. This profile contains the analysis option values.
In addition, within an Analysis Profile a Utility Profile can be specified (optional) to use also when analyzing Alter, Migrate or Compare Strategies. There is no limit to the number of Analysis and Utility profiles you can have.
The Schema Change Profile (RCM Option 0 then U-Utility Profile) lets you specify a sequence for invoking utilities that is based on the object attribute change. The utility profiles are integrated with the analysis profile options and give you more ease of use.
See: Create and Use Utility Profiles for detail on creating Analysis and Utility profiles.