Are reflection unit tokens 0 might upon copy? Either through mirror image or Leblanc's legend ability?

No, Reflection unit tokens are not 0 Might upon copying a unit.

According to the Patch Notes (2026-03-30) and the definition of Copy Effects, when a game object becomes a copy of another, it adopts the "copyable traits" of that target. These traits include the target's printed characteristics (such as Might) and its Rules Text.

While a Reflection token is created as a 0 [M] token (per Rule 184.6), the copy effect functions as follows:

1. Initial Creation: The token enters the board as a 0 [M] unit.
2. Copying: The effect then forces the token to become a copy of a target unit. At this point, the token adopts the target's printed Might and Rules Text.
3. Result: The token's Might is updated to match the printed Might of the target unit it is copying.

Important Note: As established in RiftJudge FAQ #9999 and #9410, this copy effect only applies to "copyable traits" (printed or base copied stats). It does not inherit any modifications that have been "appended or granted" to the target unit, such as temporary buffs or Might counters.