Can the repeat effect of Hard Bargain be delayed?

No, the Repeat effect of Hard Bargain cannot be delayed.

According to the RiftJudge FAQ (#816, #3433, #9328), you must decide whether to pay the additional cost for Repeat at the moment you play Hard Bargain from your hand. Because Repeat is an additional cost keyword (Rule 820), it must be paid and declared during the "Make Relevant Choices" step of playing the card.

Key Rules and Nuances:

• No Retroactive Repeat: You cannot add Repeat to a Hard Bargain after it has already been placed on the chain.
• Upfront Cost: The energy cost for Repeat is an additional cost paid upfront along with the base energy cost of the spell.
• Single Instance on Chain: Even if you pay for Repeat, Hard Bargain is only played once and enters the chain as a single object. Its effect is simply executed twice upon resolution.
• Execution Timing: Because you must commit to the Repeat when you first play the card, you cannot wait to see if your opponent pays the cost to save their original spell before deciding to use Repeat.

In summary, Repeat is not a delayed ability that can be triggered later; it is an additional cost tied to the initial playing of the spell.