Does the Pay with PayPal Wallet work, because i dont want to waste my money?
But do i need credit card or i can just pay with my PayPal ballance?
Yes it does work, I use PayPal to make purchases on the marketplace all the time without any issues.
Is there anything in particular about it you need to know?
Epic (and all non-subscription based purchases made with PayPal) are only aware of whether the payment is successful or not.
Long story short, you can use whatever payment method you want on the PayPal side, it will work just fine as long as you have enough funds to make the purchase.