After payment, you'll receive a voucher with a QR code. Use it after exchanging it for a physical paper ticket at the green machine. It can be confusing with the QR code-based direct entry ticket, but be careful, as this requires exchanging it for a paper ticket. It took about 1 hour and 20 minutes from Kansai Airport to Kyoto Station.
Easy to buy tickets and take it to register your seat yourself through the Nankai train‘s website. When using it, just use the QR Code when entering the station. The price is similar to buying it yourself and can be purchased 30 days in advance.