According to Oracle document:

Micro ETL EXECUTION plans are ETL processes that you schedule at very frequent intervals, such as hourly or half-hourly. They usually handle small SUBJECT areas or subsets of larger subject areas. The DAC tracks refresh dates for tables in micro ETL execution plans separately from other execution plans and USES these refresh dates in the change capture process.

in DESIGN -- subject areas, create copy of subject area, inactive the unwanted tasks and create NEW execution plan for this subject area.

According to Oracle document:

Micro ETL execution plans are ETL processes that you schedule at very frequent intervals, such as hourly or half-hourly. They usually handle small subject areas or subsets of larger subject areas. The DAC tracks refresh dates for tables in micro ETL execution plans separately from other execution plans and uses these refresh dates in the change capture process.

in design -- subject areas, create copy of subject area, inactive the unwanted tasks and create new execution plan for this subject area.