If multiple Arcane Artisans are creating tokens, each will exile only the ones it created.

If a card in exile has in its mana cost, X is considered to be 0.

If the card copied by the token had any “when [this permanent] enters the battlefield” abilities, then the token also has those abilities and will trigger them when it’s created. Similarly, any “as [this permanent] enters the battlefield” or “[this permanent] enters the battlefield with” abilities that the token has copied will also work.

If Arcane Artisan leaves the battlefield before its activated ability has resolved, the token that ability creates will still be exiled at the beginning of the next end step.

If any of those tokens have an ability that triggers at the beginning of the end step, that ability will trigger and resolve even if the token is exiled during the end step before that ability resolves.

If an effect such as that of Doubling Season causes Arcane Artisan’s first ability to create two tokens, its last ability will exile both of those tokens. However, if something becomes a copy of the token or creates a copy of that token later (such as Evil Twin or Cackling Counterpart), that copy won’t be exiled.