I believe that many people have thought about how Cao Cao would deal with it if Sun Quan gave the complete Guan Yu to Cao Cao. Combined with historical data, what Cao Cao is most likely to do is to release Guan Yu.
Guan Yu was very capable, and Cao Cao certainly wanted to persuade him to surrender. But Guan Yu had already made it very clear before, and Guan Yu was very grateful to Cao Cao for his tolerance, but he could not betray Liu Bei no matter what. You know, before Liu Bei had risen, Guan Yu had already done so.
I know very well that Cao Gong treated me thickly, but I was generously favored by General Liu and swore to die together, and I could not betray it.
Now that Guan Yu was a general of the Shu Han Dynasty, his determination could only be more resolute than before, and Cao Cao had spared Guan Yu before, that is, he was his master and did not pursue him. So now it's very likely that he'll do it anyway.
After all, Guan Yu's reputation is very high, and many people admire him very much. If Cao Cao killed Guan Yu, he might have inadvertently made a vendetta against many people, and Cao Cao had courage, not recklessness, so he certainly wouldn't do such a stupid thing.
The reason why Sun Quan gave Guan Yu's head to Cao Cao was ostensibly to ask for credit, but in fact he wanted to bring misfortune to Shui Dongyin, and he hoped to blame Cao Cao for killing Guan Yu. In the face of this situation, Cao Cao was very clever, and he chose to bury Guan Yu thickly, which was equivalent to directly quelling this storm.
Many people have no way to understand this matter, not that Cao Wei does not want to go to war with Shu Han, but they do not want to fall into the trap of Eastern Wu, if Cao Wei is profitable, then of course they will go to war directly.
But the problem is that this war is not for turf, but a war of revenge, and even if Cao Wei wins, they will not gain any benefit. In this case, of course, they will try to avoid war.
Cao Cao's worries were not superfluous. No matter what the name of Liu Bei's battle of Yiling was, according to the records in the Romance of the Three Kingdoms, Liu Bei was to avenge Guan Yu, so he would start a war. That is, at the beginning, the first lord was angry with Sun Quan's attack on Guan Yu and would march east.
If the person who killed Guan Yu became Cao Cao, then Cao Cao was helping Eastern Wu share the guilt. If Liu Bei really went to war for revenge, then it would not be Eastern Wu, but Cao Wei, who would be miserable.
There are also many people who speculate that Cao Cao may have spared Guan Yu because Guan Yu had spared him when he was in Huarong Dao, and logically speaking, there was no problem with this.
However, everyone should know that the plot of Huarong Dao Guan Yu releasing Cao Cao was only invented by posterity, and it did not happen at all in history. Therefore, this could not be a reason for Cao Cao to let Guan Yu go.
Of course, Cao Cao would certainly not return Guan Yu directly to Liu Bei, but would use Guan Yu to negotiate some conditions. I believe that as long as Cao Cao is not a lion with a big mouth, then Liu Bei will agree. After all, the brotherhood between Liu Bei and Guan Yu is here, and the public opinion will also tend to let Liu Bei redeem Guan Yu.
Cao Cao only took Guan Yu for benefits, while Sun Quan really slaughtered countless soldiers of Shu Han, so Cao Cao dared to guarantee that Liu Bei would never take the lead in attacking him.
After all, the strength of Shu Han is not very large, single-front operations have a certain degree of difficulty, and double-front combat Shu Han is completely unsupportable.