There are things you can do remotely. This happens all the time.
I once sued a company in New South Wales in small claims court. It was done entirely online from the US, and if there had been a hearing, it would have been by phone. The company paid up within 24 hours of the filing.
That's been true for many (not all) international suits for some time, but you can't generalize that to everywhere. In the US, things like that are set up per-jurisdiction or per-court and they all have vastly different budgets for these things. Jurisdiction is also not entirely straightforward in these instances. It's not that cut-and-dried.
I once sued a company in New South Wales in small claims court. It was done entirely online from the US, and if there had been a hearing, it would have been by phone. The company paid up within 24 hours of the filing.