Razzle

Can Razzle spawn copies of herself on a token-occupied space to remove that token? The rules say "if a unit spawns in a spawn point" — does this only work on minion spawn points?

Look for “Spawn” (instead of “Place”) keyword in the rulebook. Token rules are irrelevant here. Razzle is not a token.

Can heroes with attacks that say “after attack: perform an attack on another hero” attack two different Razzles on the same turn?

The answer is in Razzle's gold card text. Apply it exactly as written.

Can NebKher's gold copy Razzle's green to move another Razzle? Similarly, can NebKher copy Razzle's silver to despawn Razzles?

It uses "you". So no effect, since there are no "other yous" (NebKhers) to spawn/despawn.

Does Razzle get defense benefit/bane from other Razzles next to minions (ignoring the silver card for this example)?

When actions are performed (defense action is an action) each Razzle is a separate hero.

Can Min's grenade cause multiple discards if it's placed in the middle of a group of Razzles?

Active effect is part of an action

Xargatha's Stone Gaze vs Razzle: 2 Razzles are in radius, 2 are not. Can the 2 not in radius move, or does it affect all 4 equally?

The answer is in Razzle's gold card text. "each of you is the same hero, except when actions are performed."

Does a different Razzle mean a different target? If not, and the action targets a hero, does "repeat once on a different target/hero" mean the same thing?

The answer is on the Razzle’s gold. Different while actions are performed.

Do multiple Razzles count as multiple different heroes when enemies perform actions? E.g. for Garrus's "when two or more enemy heroes are in radius you may retrieve a discarded card", do two Razzle figures in radius count?

You only activate one of the Razzles as "you". The other Razzles are "other you".