There is a typo in the Compcon version of the Nelson's Skirmisher trait, it is supposed to be "Immobilized" instead of "Immobilize":

Compcon:

After attacking, the Nelson can immediately move 1 space in any direction as long as it isn’t Immobilize or Slowed. This movement ignores engagement and doesn’t provoke reactions.

Rulebook

After attacking, the Nelson can immediately move 1 space in any direction as long as it isn’t IMMOBILIZED or SLOWED. This movement ignores
engagement and doesn’t provoke reactions.

See screenshots below:

Compcon

Rulebook