On the New Yahtzee with Buddies, you can find scratchers under the 'Rewards' on the bottom of the app. Settings can be found if you click on your profile and click the drop down menu in the upper right hand corner. However, I saw nothing about scratchers on the menu.
Comment found on YAHTZEE® With Buddies: The Classic Dice Game: Scratchers
You can only start a gifting game if you:
#1 Have the new Yahtzee With Buddies update
#2. Scored enough points in the new "Weekly Challenge"
to win the dice award for that week
#3. Already own the dice awarded
You will then be prompted to:
Select a buddie to gift the dice to
(Or)
Let Yahtzee With Buddies select a player for you
(Or)
Forfeit the dice altogether
Hope this helps.
Comment found on YAHTZEE® With Buddies: The Classic Dice Game: Gifting game