Unable to manipulate internal components in imported STEP Assembly.
Solution
The internal components needed to be published after importing the step file. The part should then be editable.
Notes and References
Hardware/Software Configuration
Platform: INTL64
OS: windows
OS Version: 10_1703
Product: SOLID_EDGE
Application: TRANSLATORS
Version: V221.0
Function: STEP
Ref: 001-10055281