Find the player you want, apply for negotiation, and your scout will negotiate with the opposing club. If the negotiation is successful, he will make you an offer. If you agree to this proposal, the negotiation will be successful. If you don't agree, adjust the offer, and your scout will take this offer to talk to another club. If the opposing club agrees, the negotiation is successful; If you don't agree, the negotiation fails.
If you want to sell a player, put the player on the market (there are two ways: loan and transfer). Other clubs will pay attention to your players. When a club contacts your players, your scouts will negotiate with another club. If the conversation is successful, the scout will give you a proposal. The same is true for buying players in the future.
However, you should be careful about listing. If a player is listed, he will be very angry and will affect his state.
The value of a player is approximately equal to the salary of the player, and the transfer fee is approximately 3~ 10 times the value.