You would need to make that script compliant with what the company wants to be compliant with plus their own devops and security practices. The real sell is figuring out how to implement the bespoke human project for each company to save the money.

Also if your script just say for example picks better VM sizes you better be sure there are no outliers where the existing legacy VM size is for a particular reason, be it a reserved instance, negotiated pricing or some technical constraint. Whatever your script does I doubt you can run it as is on any client as root aws and walk away and the customer be happy.

Good luck!