Or Restore the Caliphate (name and flag change) which increases war support and decrease resistance growth, and brings along a final set of decisions such as 'Rashidun Expansion' into Iran, 'Reclaim Caucasus' with cores up to Georgia and including Van, Erzurum, and Malatya in Turkey, and 'Punish Anatolia' to take down Turkey and core the rest of it.

Proclaim the Union, which would re-core any Arabian states in MENA that aren't cored early on, along with increased stability and compliance, and a decision to move the capital to either Cairo, Baghdad, or Damascus It would add claims in other Arabian states in the Asian Middle East, and unlock 3 separate decisions to core Iraq-Kuwait, Syria-Lebanon, and Palestine-Jordan, much like Byzantium's 'Victory in' decisions.ДЄfter getting 2/3 of the 1st set, North African territories would be claimed and a second set of decisions regarding it would be unlocked so that we can core Egypt-Sudan, Libya-Tunisia, and the rest of North Africa.Д¬licking all decisions (both 1st and 2nd set) above would led to final two sets of decisions (mutually exclusive): Still, you can form it as any MENA nations. My suggestion about this is to cut down the initial required states to just need to control the entire Arabian Peninsula (not including Trucial States, Aden, and Qatar, which would be claimed despite them being held by UK).

As you can see, forming Arabia is quite chalenging, as you need to fight both Axis and Allies to get all the required territories BEFORE forming it.

Hoi4 waking the tiger formable nations