In Germany we have two different Trainer Cards with the same translation for the name. Both Energy Retrieval and Energy Returner are called "Energie - Rückgewinnung". How would this be handled in a Decklist? Can I have 4 of both?

In Japanese and English those are two different cards with completely different actions. You may have up to 4 of each in your deck, but on the decklist you should list them on separate lines and include the set and card number on each line for clarity.

Relevant cards