Would combining sort and partition-by be close to what you are asking for?
(->> [:a :b :c :a :b :c] sort (partition-by identity))
((:a :a) (:b :b) (:c :c))
(->> [[:a :b :c] [:a :b :c]] sort (partition-by identity))
(([:a :b :c] [:a :b :c]))
and if you need them to be vectors after:
(->> [:a :b :c :a :b :c] sort (partition-by identity) (map vec) vec)
[[:a :a] [:b :b] [:c :c]]
(->> [[:a :b :c] [:a :b :c]] sort (partition-by identity) (map vec) vec)
[[[:a :b :c] [:a :b :c]]]