REQUEST

Highlight the partner's item and select it with the X button.
Then, select the REQUEsT command and press the X button again.
In this way, you can request that item.

Remember that these AI-controlled characters can and will
occasionally refuse requests based on how well they get along with you.

PRESENT

Highlight the item you wish to offer and select it with the X button.
Then, select the PRESENT command and press the X button again.
You will hold out the item and offer it.