Let's See My Favorite Alternate Fusion-Xs are:
Zombie-X (i would love to draw zombies versions of merged modes).

Fusion-X 63 (i wanted to make a female version of nicholas).

Fusion-Xi (creative idea).

Fusion-X 28 (having a version of Onawa as Fusion-X was an idea i had for a long time during my first season).

Fossil-X (another creative idea).

Nega-X (i have this vibe if he and fusion-x prime fight each other).