Can a dice removal from an event yield the reward from a Character action at the same time?

For Example if you play Bolt Hole "Remove one of your Yellow Character Dice to give that Character 2 shields" be played and if the Dice that you remove is for example Guavian Enforcers do you also get to remove 1 shield from a Character at the same time? due to the Action on the Guavian Enforcer Character Card - Remove this die to remove 1 shield from a Character. Or would this constitute 2 actions?

The Guavian Enforcer ability is an action and not a trigger condition, therefore, playing the card and doing his action are two separate actions and can't be combined into one.

Lusiphur05 is correct.

Otherwise if you played Swiftness: "Your next card played gets the ambush keyword" you could, as Bolt Hole would also have ambush. Which would allow the 2 actions needed to do it all on our turn.

You can't actually play Swiftness > Bolt Hole > Guavian action, because once you've played bolt hole, the Guavian die is no longer in your pool. You can't remove the same die twice.

Nice, I missed that one. Thanks.

Some effects have a cost - you have to 'pay' something to get the effect.

Both Bolt Hole and Guavian Enforcer require you to remove a dice as the cost; and you can't pay with something that you don't have. If you triggered one, you would not be able to pay the other.