If the Groom and witnesses are in one place physically and Bride is attending via Zoom Call is the Nikkah Valid.
for context Women is an adult, who has been divorced before and looking to remarry. for few reasons she can't physically be in the same location for the time being.
And it is not possible for her to appoint a Wakeel on her behalf but she will be present via Zoom/Skype Video call at the same time.
بسم اللہ الرحمٰن الرحیم
الجواب منہ الصواب
For marriage to take place, it is necessary for the bridegroom-to-be or his lawyer to be present in the venue of Nikah Ceremony (Majlis-e-Aqd) and to have the “proposal and acceptance” pronounced in the presence of two witnesse; without it there is no marriage. But, if the bride-to-be is at another place and proposes or accepts the Nikah through Zoom, Nikah will not be valid.
However, in the situation in question, there is an option to validate the Nikah, if the bride-to-be by herself and directly appoints her husband-to-be or assigns another person as her lawyer or representative, and then either of those two men confirm the proposal and acceptance on her behalf, in presence of the two witnesses, in the venue of the Nikah ceremony, then that marriage will be solemnized otherwise not.
واذا اذنت المرأۃ للرجل أن یزوجھا من نفسہ فعقد بحضرۃ شاھدین جاز (ھدایۃ فصل فی الوکالۃ بالنکاح وغیرھا)
فقط واللہ اعلم بالصواب