That depends on what you mean by "effects already on battlefield". The only things it interferes with are triggered abilities based on entering the battlefield (and only if it was a creature that entered). Note that the creature that entered the battlefield does not need to be the source of the ability.
It does not stop activated abilities.
It does not stop static abilities.
It does not stop replacement effects, even those that modify entry to the battlefield.
It does not stop triggered abilities based on other events.
If you mean something like "Whenever a creature enters the battlefield under enchanted player's control, that player loses 1 life and you gain 1 life."
on Trespasser's Curse, that is absolutely stopped by Torpor Orb.
A) Metallic Mimic itself doesn't get counters off its abilities anyway.
B) "Each other creature you control of the chosen type enters the battlefield with an additional +1/+1 counter on it." is not a triggered ability.
603. Handling Triggered Abilities
603.1. Triggered abilities have a trigger condition and an effect. They are written as “[When/Whenever/At] [trigger condition or event], [effect]. [Instructions (if any).]”
Edit: What is the proper procedure to notify the powers that be about a card misspelled, e.g. Tresspasser's Curse [sic]?
That depends on what you mean by "effects already on battlefield". The only things it interferes with are triggered abilities based on entering the battlefield (and only if it was a creature that entered). Note that the creature that entered the battlefield does not need to be the source of the ability.
It does not stop activated abilities.
It does not stop static abilities.
It does not stop replacement effects, even those that modify entry to the battlefield.
It does not stop triggered abilities based on other events.
If you mean something like "Whenever a creature enters the battlefield under enchanted player's control, that player loses 1 life and you gain 1 life."
on Trespasser's Curse, that is absolutely stopped by Torpor Orb.
[c]Torpor Orb[/c] -> Torpor Orb
[c]Metallic Mimic[/c] -> Metallic Mimic
A) Metallic Mimic itself doesn't get counters off its abilities anyway.
B) "Each other creature you control of the chosen type enters the battlefield with an additional +1/+1 counter on it." is not a triggered ability.
Edit: What is the proper procedure to notify the powers that be about a card misspelled, e.g. Tresspasser's Curse [sic]?