May one make a video call to see a prospective spouse who lives far away?

Yes, in place of seeing each other in person, under the same conditions as looking at a prospective wife during khitbah (an-nazar).
The purpose of seeing is so that the decision to marry is made with clarity, and this can be achieved through a video call when distance makes meeting difficult. The conditions: a serious intention to propose, the woman dressed covering her ʿawrah (only the face and palms may be seen according to the Shafi'i school), the call is accompanied by or known to the wali or family members, and it is not recorded or shared without permission. Avoid prolonged one-to-one video calls, as the ruling resembles khalwat in terms of temptation. For cross-border ta'aruf, involve both families from the start. See khitbah.