Add discount rule for customers, they will get X% off, if they pay via crypto instead of fiat currency.
Enable order discount for your customers inside your Woocommerce store if they pay via cryptocurrency in a specific token where you have added a discount rule, suppose you added 5% discount for USDT so customers will get 5% discount on their order if they make a payment via USDT.
Custom Token & Discount
Yes, accept payments in your own custom token and provide discount to your users if they pay via your custom token.
Fiat vs Crypto Offers
If a customer will pay via fiat currently then he need to pay full, he will get a discount only if he pay via a cryptocurrency mentioned by you.