ERC721 Tokens – Paying for ERC721 Tokens with ERC20 Tokens Instead of ETH

Use the ERC-1155 standard for this: https://eips.ethereum.org/EIPS/eip-1155

Core Idea: Aims to be a combination of the ERC721 and ERC20 standards. Enables batch transfers (to multiple parties!) to make stuff cheaper. Combination explanation here, but general idea is to have another mapping:

💩 ERC721: mapping id ⇒ owner

🧠 ERC1155: mapping owner ⇒ id ⇒ balance

Ex: me ⇒ 0 ⇒ 200

OpenZeppelin has a ERC1155 contract that might be useful. In order to be compatible with ERC20 and ERC721 schemes, you might need to add some functions, but the basic structure is here

The order matching information -- buy order, sell order -- is not saved or accessible on chain in a way that your contract can be read during transfers.

There is some way to do what you are saying, but it is not necessarily what you want.

You can disable all ERC-721 transfers in your contract unless they are initiated by your contract itself. So you create your own match order function to evaluate the atomic order and only put the order through if you like it.

This means people cannot buy/sell on OpenSea directly, but they can take those orders and execute on your website.