Can I play cards on Pokémon with Omega Barrier / Unnerve for no effects?

[DaddyPlaysTCG]

Are there any no-effect-from-public-knowledge legal card plays?

Why this question:
The two compedium answers referenced below seem to imply that my Lysandre or Guzma can target my opponent's benched Pokémon with Omega Barrier or Unnerve for no effect, but don't confirm it.
The compendium answer about Eneporter & Unnerve possibly refers to this issue, but is not clear.
The compendium has helped a lot but in this case I don't know if I can e.g. burn a Field Blower on Pyroar's tool. Is it the case that a card be played, even for no effect, when that card could be played (with an effect) if Omega Barrier and Unnerve were ignored? What's the general rule?

Suggestions:
1. If Lysandre and Guzma can't be played for no effect, expand the two compedium answers to make that clear. If they can, consider just stating that in those answers too.
2. Do something about the Eneporter vs. Unnerve compendium entry...

References:
Omega Barrier Ancient Trait (Primal Clash #86 Primal Groudon-EX):

Whenever your opponent plays a Trainer card (excluding Pokémon Tools and Stadium cards), prevent all effects of that card done to this Pokémon.​

Unnerve Ability (Forbidden Light #19 Pyroar):

Whenever your opponent plays an Item or Supporter card from their hand, prevent all effects of that card done to this Pokémon.​

Compendium answers that seem to imply no-effect use ("you do not get to switch" rather than "you would not get to switch so you can't play Guzma"):

Q. If I use Guzma and choose my opponent's Primal Groudon-EX that has the "Omega Barrier" Ancient Trait, do I still get to switch my own Pokemon?
A. Since Omega Barrier prevents the first effect of Guzma, you do not get to switch your Pokemon. (Aug 31, 2017 TPCi Rules Team)

Q. If my opponent's Active Pokemon has the "Omega Barrier" Ancient Trait, can I use Lysandre to switch one of my benched Pokemon with it?
A. If your opponent's Benched Pokemon has "Omega Barrier", then Lysandre's effect will be blocked. But choosing a Benched Pokemon without "Omega Barrier" will cause it to switch with the Active Pokemon because the Benched Pokemon is the target of Lysandre. (Apr 9, 2015 TPCi Rules Team)

Please note there's a typo in the second question: not "my benched Pokémon" but "his benched Pokémon" or "my opponent's benched Pokémon".

Unclear compedium answer about Unnerve:

Q. Can I play Eneporter to try and fail to move a Special Energy onto a Pyroar that is protected by its "Unnerve" Ability, or would I not be able to play Eneporter at all?
A. The fact that its effect will be blocked by another effect such as Unnerve does not prevent an Item or Supporter card from being played. For example, your opponent may play Eneporter to try moving a Special Energy and Pyroar is a valid target, but Unnerve blocks the effect even though Eneporter was played. Playing a card for no effect happens when the game state itself prevents any effect from taking place and in that case the card would not be played, but that is not what this example is referring to. (Forbidden Light FAQ; May 3, 2018 TPCi Rules Team)

Unclear points:
1. The effect of Eneporter, if any, is not clearly described. Wouldn't Unnerve just block the attaching part of Eneporter's effect, with the result that the Special Energy is discarded?
2. The last sentence seems to be an unclear answer to an unclear implicit question, possibly the question I'm asking. Does it allow or forbid no-net-effect card play? "The game state itself", whatever that is, should include the presence of an active Unnerve ability, right?

tl;dr:
Please clarify when a card can be played for no effect as known from the public game state, if there's such a thing, and if there's not, consider making some compendium answers clearer.

 

[PokePop]

You are confusing "doing something for no effect" with "doing something and the effect being blocked".
Those are not the same thing.
They may wind up with the same result, but they are different.
So you can play something that has a valid target for its effect, and then an Ability (or something else) could negate that effect from taking place.
You can play Field Blower and target the tool on Pyroar, and then its Ability will block that effect from completing.

Yes, that should be clarified that the Special Energy would move off of its original location and then be discarded when trying to attach it to Pyroar.
Or, if it starts off on Pyroar, then it can't be moved from it.