Hello @EricYu
Thank you for your interest in the seven25 subscription. You can also buy the subscription, of course. Basically, anyone can buy a seven25 subscription. No matter where they live.
What you need to buy the seven25 subscription is a Swisspass card and a customer number. If you do not yet hold a travelcard or a SwissPass, you can still buy your new seven25 Travelcard online. If you are buying a travelcard for the first time, we need to verify your identity. You will need your passport or ID card and a smartphone with a camera. You will also need a recent, high-quality, digital passport photo, for the Swisspass card.
You can find more detailed information about the purchase options under this link: Help with the seven25 Travelcard | SBB help & contact
Have a great day, StéphanieB
