How do you get a scenario in which Malays, to avenge British colonization of their country, decide to fight the British? What would it need for this scenario to take place?
How about several secret societies, such as Malay nationalist ones similar to the Kuomintang? Even interesting if they can fight Britain outside Asia, such as in Europe, along the lines of the Polish legions. Or, how about the Malays being treated like the Indians in their home country? Perhaps they can in 1914 bring rebellion [at least after October 1914] or try to sail by ship to Central Europe and persuade the kaisers to build up Malay legions for use on the Western or Middle Eastern Fronts? Or they can get to East Africa, but since they won't like colonization, they would just ignore.IIRC in the early 1900s the British initially instituted more centralising policies before changing their minds and decentralising in the 1920s onwards so I suppose you could try using that. It's a rather large challenge though as there doesn't appear to have been all that much discontent, at least amongst the rulers of the Unfederated Malay States who had a fair amount of autonomy, and the Federated Malay States did pay for the building of the battleship HMS Malaya.
Not in otl circumstances but if several revolutionary parties are formed to campaign for Malaysian independence, they might contact aid when they revolt. They don't need Ottoman aid, they can get German aid through secret blockade running and smuggling from Thailand and present day Indonesia. [From German and neutral merchant ships and sailing boats]Even though the Malays are mostly Muslim, would Turk dominated Ottoman really offer that much assistance and if so, were they in a position to get any substantial help to the Malay States?
Of course, this is my point.It's not going to give substantial change to the war I think.
Will it be widespread though? If the general attitude of the Malays became anti-British, the British might favor the Chinese in Malaya instead?
How do you get a scenario in which Malays, to avenge British colonization of their country, decide to fight the British? What would it need for this scenario to take place?