You may refer the following Note for details about, Types of Attributes Masked
Using Oracle E-Business Suite Release 12.1.3 Template for the Data Masking Pack with Oracle Enterprise Manager 11g (Doc ID 1437485.1)
Using Oracle E-Business Suite Data Masking Pack, Release 12.1.3 with Oracle Enterprise Manager 12.1 (Doc ID 1481916.1)
Using Oracle E-Business Suite Data Masking Pack, Release 12.1.3 with Oracle Enterprise Manager Cloud Control 13c (Doc ID 2216575.1)
Hope this hleps
I think the note is only for hrms module.
I am using this.
You may try Section 3: Customization for possible option as the ideal attributes that are masked are as mentioned in the Note