While Goodra's "Slimy Room" Ability is active, if I use an Ability or card effect like Swampert's "Muddy Maker" Ability to attach an Energy card from my hand but flip tails, can I use that ability or effect when I try again with another energy?
No. The Ability has been used and the energy is discarded even though your regular Energy attachment for the turn has not been used up.
Source: Fusion Strike FAQ; TPCi Rules Team (2021-11-11)

Relevant cards

Note: All applicable cards may not be listed below.
SWSH8_197
SWSH8_197
SWSH8_64
SWSH8_64