I look for the opposite of "invariant" in the context of scientific language. If you look at this example sentence:

[...] Although it is translationally and rotationally invariant, it is not permutationally invariant. [...]

there is a repetition of the word "invariant" and a double negation. ("not" and "in-" as prefix)

Since I could not find any example of people saying "variant" for "not invariant", I do not know how to nicely write this sentence.

If I look at Merriam Webster and list the possible antonyms: "changing, deviating, nonuniform, unsteady, varying"

I think none is fitting, but I am also not of English mother tongue.

I look for the opposite of "invariant" in the context of scientific language. If you look at this example sentence:

[...] Although it is translationally and rotationally invariant, it is not permutationally invariant. [...]

There is a repetition of the word "invariant" and a double negation. ("not" and "in-" as prefix)

Since I could not find any example of people saying "variant" for "not invariant", I do not know how to nicely write this sentence.

If I look at Merriam Webster and list the possible antonyms:

changing, deviating, nonuniform, unsteady, varying

I think none is fitting, but I am also not of English mother tongue.