What is "Sell Instant" in Copy Trading?

Sell Instant determines if you want to frontrun / backrun the target trader's sell transaction.

If you tick Sell Instant and set the Frontrun Gas Multiplier higher than 1, then it will frontrun the target's transaction.

If you tick Sell Instant and set the Frontrun Gas Multiplier to 1, then it will backrun the target's transaction. Backrunning ensures that the transaction is in the same block as the target trader's purchase but confirmed after his transaction.

If you untick Sell Instant, then it will use Normal Gas Multiplier to send your transaction and this will happen after the target trader's transaction is confirmed.