Hi Adhi
MDG always considered field properties defined in target ECC system which is imported into MDG also. More over if you want to make any field as required (Addional only in MDG) you can do it in Edit Data Model >Entity Type >Attribute: select Required check box for concened arritubes.Or if you want dynamic field properties also we can do it in validation and derviation
Example for MDG-M
If you make old material field as required in T130F (ECC customisation in OMS9) it automatically becomes required. In addition if you want to make any other field as required in MDG you can make as per below
