All perfect praise be to Allah, the Lord of the worlds. I testify that there is none worthy of worship except Allah and that Muhammad, sallallahu ʻalayhi wa sallam, is His slave and Messenger.
If a person had a wet dream but did not see a discharge of Maniyy (semen), he is not required to perform Ghusl, because Ghusl becomes due upon seeing the discharge of semen.
The Kuwaiti Encyclopedia of Fiqh reads, “If a person has a wet dream but does not discharge semen, no Ghusl is required. ʻAa’ishah, may Allah be pleased with her, narrated that the Prophet, sallallahu ʻalayhi wa sallam, was asked about a man who finds wetness and does not remember having a wet dream. He said, ‘He should perform Ghusl.’ He was also asked about a man who had a wet dream but does not find wetness; he said, ‘No Ghusl is required of him.’”
Moreover, An-Nawawi wrote, “Ibn Al-Munthir quoted the consensus of the scholars that if someone has a wet dream or engages in sexual intercourse (in his dream) but does not discharge semen, he is not required to perform Ghusl.” [Al-Majmoo’]
Accordingly, you are not required to perform Ghusl if you do not discharge after seeing the wet dream.
Allah knows best.