Is there a reason that Moltres, Zapdos, and Articuno don't have extrasensory under transfer only moves?

Question

The gen one legendary birds can have extrasensory as a move via a trade from Pokemon XD: gale of darkness. Im not involved in competitive Pokemon beyond watching a few games here and there on youtube, so Im not really sure if this was not included because of balance reasons; I figured it was worth asking.

Comments

I believe it may have been overlooked.

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Isn't Extrasensory a tutor move?

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In Gale of Darkness, yes. But when you transfer it to ORAS, it becomes a transfer-only move.

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Dang..

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This site has been almost all about core series games from the start. I'm not sure if XD move tutors will ever be included.

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XD and Colosseum kinda count as core games, but idk. The problem though is that aforementioned pokemon can have Extrasensory in ORAS, but it isn't mentioned.