Your request is interesting and I voted for it; it might not come up all the time but would be helpful at times.
You could implement the Eisenhower Matrix easily in Asana, if you’re willing to forego the precise 2x2 presentation. Create a single-select custom field with four values, one corresponding to each box, then in List view group by that field:
If you really want the 2x2 visual representation, I offered that a long time ago in Asana2Go (Disclaimer: I’m the creator):
Thanks,
Larry

