Hi Sin5k4,
This is not.possible using the current form as these attributes are in another table. First a party record needs to be inserted before you can add e.g. a phone number. So any validation will not be possible on dirpartytable methods.
You can create a new creation form where there are next to some basic party fields also (unbound) fields for a phone number and address. Then you can have a check to have these fields mandatory before saving the record. A simple similar scenario can be found in standard AX when you create a new legal entity. The creation form here has the Country mandatory. At closing this creatiom form the country is saved in the address of the legal entity.