If I use Forretress ex's "Exploding Energy" Ability, can I attach any of the Energy cards that I searched for to Forretress ex before it is knocked out?
Yes. They would then be discarded with the Forretress ex.
Source:
Paldea Evolved FAQ; TPCi Rules Team (2023-06-08)
If I bring up Weavile with the "Assaulting Hunt" Ability after my opponent KO's my Active Pokemon, can I switch in 1 of their Benched Basic Pokemon to the Active Spot?
No, because Assaulting Hunt only works "during your turn"
Source:
Paldea Evolved FAQ; TPCi Rules Team (2023-06-08)
Can you use Manaphy's "Pulling Currents" attack when your opponent has a full bench?
It's public knowledge that you can't put down any additional Basic Pokemon on your opponent's full Bench, so although the attack can be used you cannot look at your opponent's hand and you cannot put any additional Basic Pokemon on your opponent's Bench.
If my opponent has Duraludon VMAX with the "Skyscraper" Ability in play, when I use Inteleon VMAX's "G-Max Spiral" attack and choose to return the only Special Energy card attached to Inteleon VMAX to my hand, does "Skyscraper" prevent the damage or not?
The choice to remove the Special Energy card is made first, but then damage is done and finally effects of the attack. So removing the Special Energy card is an effect that doesn't happen until damage has been done and therefore blocked by Skyscraper.
If I have Venusaur with the "Jungle Totem" Ability in play, and I use Typhlosion's "Blazing Energy" or Charizard's "Energy Burn" Ability while it has a Basic {G} Energy attached, how much {R} Energy would be provided?
A. Each Basic {G} Energy provides {R}{R} Energy. Even though the Energy type provided changes from {G} to {R}, the card name is still Basic {G} Energy, so Jungle Totem still works.
If my Lumineon V attacks with "Aqua Return" to take my last prize card, but Lumineon V is my only Pokemon in play, do I win because I took my last prize before shuffling Lumineon V into my deck or do I lose because Lumineon V get shuffled in before taking my last prize?
Everything has to resolve before you check for win conditions, and in this scenario both players have achieved one win condition; the game would then be resolved by either Sudden Death or a Tiebreaker Game. However, if the opponent also has no remaining Benched Pokemon then they would lose due to 2 win conditions vs. only 1!