It would be simple to do - An EO can reaffirm a constitutionally protected right. It wouldnt even be contended (by anyone serious.
You dont understand what an EO does.
EOs only apply to federal government workers and they do not negate state or federal laws.
Do you have a different argument?
This type of EO is perfect though - It does not establish a new rule, it’s a federal edict that enforces a constitutional rule.
The constitution is federal and the states do NOT have the right to negate any of the enumerated rights. The 10th amendment allows states some degree of decisions but nothing that can interfere with the original bill of rights or the constitution.
An EO would be effective not to establish a new rule, but to enforce those that are original constitutional law. The states CAN NOT declare laws that differ from the federal constitution when it comes to the 2nd amendment. All of the local and state laws in this regard are illegal and illegitimate.