The plural of rendezvous is rendezvous.
A rendezvous is a planned meeting or gathering between individuals at a specific time and place. It is often used to describe a meeting that is arranged in advance, especially for romantic or secret encounters.
Rendezvous can also refer to a designated point or location where people agree to meet or converge.
Singular:
Plural:
Sources:
https://www.collinsdictionary.com/dictionary/english/rendezvous