Two people want to exchange cars, Alice owns Honda CRV and Bob owns Toyota RAV4.
Honda CRV represented by 1 satoshi at 1qwe...
Toyota RAV4 represented by 1 satoshi at 1rty...

Bob and Alice construct single transaction to exchange cars:
Inputs:
1 satoshi from 1qwe...
1 satoshi from 1rty...
Ouputs:
1 satoshi to 1asd... (address owned by Alice)
1 satoshi to 1fgh... (address owned by Bob)

Is it possible to know what car owned by Alice, or did I misunderstand the statement that exchanged items has to be a part of the same transaction?