Is it permissible to join first 2 rakath of Esha Salat with the Taraweh Jamat and then continue on his own?

According to Sunni scholarship, as reflected in Tafsir Ibn Kathir, there is a precedent for combining prayers when necessary. The Prophet Muhammad ﷺ was known to delay the Maghrib prayer to combine it with the Isha prayer when he was in a hurry to travel, as narrated in Sahih al-Bukhari: I saw the Messenger of Allah (peace be upon him), when he was in a hurry to travel, delay Maghrib prayer so he could combine it with Isha. Sahih al-Bukhari 18:29SunniSAHIH. This indicates that combining prayers can be permissible under certain circumstances.

On the other hand, according to Shia scholarship, as reflected in Majma al-Bayan, the practice of performing prayers in congregation is also highly regarded, but specific rules apply regarding the performance of Taraweeh. The Shia view emphasizes maintaining the integrity of each prayer and suggests that it is preferable to perform the prayers as separate entities rather than combining them unless there is a legitimate reason to do so.

Ultimately, for a ruling that applies to your specific situation, it is best to consult a qualified local scholar who can provide guidance based on your circumstances and the practices of your community.