Suppose you received an electronic gift card at Piggy.Cards, some brands like Home Depot allow you to put the gift card inside digital mobile wallets like Apple Pay (Please see the image below) and Samsung Pay.
Then you can use those gift cards offline through digital mobile wallets.
If a gift card doesn't support digital wallets like Target gift cards, you can print out the gift card or have the screenshot of the gift card with the bar code and scan the bar code upon checking out in physical stores.