Chinese Nationalist Front
An underground organization in Eastern China that has been fighting against Japanese rule since China's conquest by the latter in 1941 (world where the U.S didn't place sanctions against Japan for various reasons) and conducts various terrorist activities such as bombings, killing of Japanese citizens and Chinese that work with the Japanese, robberies, suicide bombings and partisan attacks on Japanese controlled installations.
It has a significant amount of support from the Chinese populous and seeks to establish a nationalist government with fascist tendencies which leads it to clash with the Chinese Communist Brigade (a rival underground faction descended from Mao's faction of Communists).
The Nationalists are supported in secret by the U.S and by powerful Chinese that are overseas who seek to weaken the Japanese Empire.
Pakistani Jihadists
Formed in the early 1950's in the aftermath of India's conquest of Pakistan after a war caused by the murder of Gandhi by a muslim extremist, the Pakistani Jihadists seek to drive the Indians out of Pakistan through terrorist acts. They've been responsible for the murders of large numbers of Indians, engaged in robberies, bombings, kidnappings, hostage situations and numerous other terrorist activities.
What makes this movement so dangerous is that it's not a centralized group hence why it's survived for so long. The Jihadist cells themselves vary on political opinions. Some want to wipe out the Indians while other merely want their nation back. Some are Anti-Western while others are pro-Western. Some are Pro-religious while others are Pro-Marxist. The one thing that they all have in common is their desire to free Pakistan from Indian rule.
Sons of New France
Formed in a world where New France was given back to the French following the end of the seven years war only to reconquered permanently by the British during the Napoleonic Wars in the early 19th century, the Sons of New France seek to drive the British from New France or "Quebec" as they call what's Canada in OTL.
Similar to the Irish Republican Army in OTL, the Sons of New France have been on and off engaging in terrorist activities against the British authorities and any British civilians. In the past when the British directly ruled "Quebec", the movement was mainstream but with Quebec gaining home rule in 1965, the most virulent versions of this terrorist movement died out only to be reborn in 1987 following the British refusal to allow Quebec to control its own foreign policy.
However, the current Sons of New France movement is but a shadow of its former self and is regarded as a fringe movement.