As the title asked. Can you use one of your actions to use whisky on another investigator? Or do you have use a trade action first? Ad then that investigator can use whiskey ? Thank you

auctions

Depends on the text on Whyskey. If the text calls out for "any investigator", then, yes. Otherwise, then, no, it's trade first and then use the item. Thematically, I think it's the latter of the two. In any case, when asking about cards, it's always better posting the text on the card so that feedback may come faster and from more people (pulling out the game and checking cards is not always feasible)

Great thank you. I'll do that in the future