The Priestesses embody the connection between the living force present in all lifeforms, and the greater cosmic force: https://i.imgur.com/vklRZnb.jpg
-SW.com
The Ones were embodiments of the cosmic force itself: darkness, light, and neutrality.
So if The Ones were hard-pressed to contain Abeloth, it's very unlikely that The Priestesses would be able to do so. There is a big difference between them, tbh.
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"I am tired of Earth. These people.
I am tired of being caught in the tangle of their lives."