If I have Eye of the Herald but my unit gets killed with Hidden Blade as a reaction during move trigger, will I still have recruit after my unit dies or no, because the Eye of the Herald will be returned to base?

No, the Recruit token will not be created.

Here's why: When your unit moves, Eye of the Herald's trigger goes on the chain. Your opponent then plays Hidden Blade in response, killing the unit. Even though the gear itself detaches and stays at the battlefield, the triggered ability is appended to the unit's rules text, not the gear's. When the trigger tries to resolve, the unit is in the trash with no board location, so "here" returns null and the instruction fails — no token is created.

This is the same principle as bouncing the unit with Gust (FAQ #9629): once the unit leaves the battlefield before the trigger resolves, the ability can't determine where "here" is and does nothing.