Correct yes they are offering scan configuration options
1) OAS is the always ON scanner - scanning Read/Writes - you can turn this on or off - all scanned/nothing scanned in OAS
2) You can have OAS turned on and then scan configure to scan ONLY reads or ONLY writes by removing whichever tick you wish.
3) Exclusions again you could have OAS on and scanning reads/writes but choose not to scan filetype extension or like database dir structure.
OAS and ODS configs are different.
For ODS - go into ePO Task Catalog - select product - on demand task - create a new task
This has its own configuration option for each task you create.