Nimis + Kalandra's Touch

What would happen?
Projectiles with Nimiz alone often travel behind me (= away from me).
Would they return to me again?

(cant test because i have no Kalandra' Touch)

nothing. "Projectiles Return to You" is an absolute modifier that only acts once and cannot be negated. Very similar to something like Loreweave's "Your maximum resistances ARE x%". There's also the idea that returning projectiles are not "projectiles" anymore but, in fact, RETURNING projectiles and thus can't be further modified. Similar to the pierce/fork/chain mechanics

Or I guess the best example would be using Kalandra with a ring enchanted with "Your meteor towers leave burning ground". You can't leave burning ground...and then leave burning ground again. It happens only once.