1. Withdraw from CHP with Export Private Key in Electrum --> Spent the coins.
2. Withdraw from CHP with Export Private Key in Electrum --> Sweeping in Electrum --> Spent The coins.
3. Sweeping directly from CHP to an Wallet --> Spent the coins.
Questions to clarify before answering:
1. Does "CHP" stand for a ChipMixer chip? Do you mean Import instead of Export?
2. I'm confused: you get the private key from chipmixer, you don't export it from Electrum.
Generic answer:
When sweeping a private key, it gets added to your wallet. If you already had coins in that wallet, they may get linked together when you make a payment and don't use Coin Control. The Electrum server may also be able to link several of your addresses together.