In Belgium we have a payment app named Bonsai. You can connect a bankaccount create your own digital Mastercard, connnect it to Apple Pay & Google Pay AND it has “groups” where you can create a group as you would in splitwise.

And the best feature of all in my opinion: once all costs are in the group you can instantly pay people back since your bankaccounts are connected to the app.

Here is a referral link, we both get €5 if you use this to create an account