In the event of a cock block where one male cock blocks another male, the blocking male may attempt to steal the opposing male's target and swap the blocked cock with his.
This is usually done out of spite of the blocked male.

When you think up something brilliantly righteous while baked.

Whereas 'Cockblocking' is the act of preventing someone from getting laid, the act of 'Cockswapping' is when the swapper purposely blocks the sexual attempts of a third party, only to move in after they've ruined everything for their own personal gain.

A cockswapper knowingly uses lies, money, or any other means to steal a potential sexual partner from someone else.

A cockswap can be performed by men and women, however is mostly used as a term by men, as women usually just call the offending party a 'slut'.

When two girls mutually agree to "swap" their respective boyfriend's cock for the other's.

Cock swap is when one party cock blocks, only to replace said lost cock with an alternative one.

The act of cumming in someones mouth then spitting it onto someone elses cock

Whe you cockblock someone who was gonna cockblock you only if it's between males.