The value is subjective. If the buyer values the shoes at 10 yuan and the seller values 10 yuan at 10 yuan then from economic perspective equal amount of value was exchanged (i.e 10 value of yuan embedded in paper notes for 10 value of yuan embedded in shoes) regardless of what were the costs of production costs.
Also money just serves to solve double coincidence of wants ultimately people exchange just goods and services for another goods and services. In microeconomic exchanges like buying shoes money does not matter at all.
Response to edit of a question:
I think that your confusion stems from not understanding the definition of value. Goods in economics dont have value based on their cost of production but value is determined subjectively. That is if a shoe leather costs \$10 and labor used to produce shoe \$30 that does not mean that shoe has \$40 value. The value of shoe that costed \$40 to produce can be anything in range $[0,\infty)$. The value depends on the customer subjective valuation. If shoe that costed shoemaker \$40 is by all consumers valued at \$ 0 then that is the true value of the shoe. If all consumers believe that the shoe has value \$100,000 then that is it's true value.
Going back to the exchanges, which is your question about there can be only 4 kinds of exchange (where the world exchange implies that the transaction is voluntary i.e. no theft or something like that):
- Both from seller and buyer perspective equal value is exchanged. That is both buyer and seller value shoe at exactly \$100.
- From buyer perspective equal value is gain but from seller
perspective more value is gained. For example, buyer values shoe at \$100 so buyer exchanges \$100 for the shoe, but seller only values the shoe \$40 so seller has \$ 60 gain in value.
- from buyer perspective
more value is gained but from sellers perspective equal value is
gained. Buyer values the shoes at \$ 100 and seller only asks for \$40 and seller values the shoe at \$40.
- both parties gain more value. Buyer values the shoe at \$ 100 and seller at \$ 40 but they agree on price \$ 50, so buyer gained \$50 of extra value and seller extra \$10
The case 1, and 4 can be seen in standard Demand and Supply diagram below
At exactly equilibrium price where S=D the last buyer and last seller exchange exactly the same value as they both value the good at exactly the same price (case 1). Left of the equilibrium price both seller and buyer get surplus value (case 4). A case 2 and 3 could be showed on a Demand and Supply diagram where in the first case supply is flat and in a second case demand is flat (I did not wanted to add too many pictures to my answer so I left only this one I trust that you can imagine either of them being horizontal flat lines. Right of the equilibrium price no exchange is possible as in that area either buyer or seller would actually experience value loss from transaction. A sane person would never enter into exchange where the person would loose - in that case either the person is not rational or the person was coerced hence we are no longer taking about exchange but about theft or scam.
To sum it up: In an exchange, which implies voluntary change of something for something else there cannot be any loss. There can be only equal exchange which is the minimum condition for exchange to occur at all, or there can be exchange where both, or one of the parties benefit. But there can be no losses. Empirically majority of exchanges involve exchange where both parties benefit, however since you are asking if there could be equivalent exchange the answer is yes, it is the marginal exchange on the market and all other previous exchanges had to be either mutually beneficial or equal for one side while being beneficial for the other side.