They can... But may they is the real question
Oath
Generally, individuals are expected to adhere to the exact wording of an oath of allegiance, as it holds legal and symbolic significance. Altering the words can undermine the integrity of the oath and may not be recognized as valid. However, in some cases, individuals may request modifications for personal or cultural reasons, but this typically requires approval from the relevant authority. Ultimately, adherence to the prescribed wording is usually necessary to fulfill the legal requirements of the oath.
I heed to an oath.
The oath appears in the US Constitution.
The witness should look at the person administering the oath when taking the oath.
If you exclude the oath taker’s name, the first four words are: “I do solemnly swear.”
A pauper's oath is a sworn statement or oath by a person that he or she is completely destitute or a pauper, i.e.without any money or property
An alter ego is an alternative identity of a person, or a close and intimate friend.
I hereby declare, on oath
Alternate, alternative, alternating, alter-ego, falter.
a person who swore that the accused was innocent