Just a quick little worlda I made from this post and this post, nothing too special.
Long story short, Chiang Kai Shek doesn't become leader of the KMT, instead the left wing of the KMT ends up holding power after Sun Yat Sen dies. The United Front continues, and the Communist Party of China grows in influence. Japan still invades Manchuria, but since the Nanjing government isn't busy trying to purge the communists in the encirclement campaigns, Zhang Xueliang isn't left to fight the Japanese alone, and the armies of the central government as well as other warlords (and later the USSR as well) join the fight in Manchuria. After a few years of fighting, Japan is pushed off the mainland and sues for peace, giving China back the territories it had lost since the Treaty of Shimonoseki, giving up control of Korea, and giving Sakhalin and the Kuriles to the USSR. In the aftermath, the Communist Party, now very influential in both the KMT and China as a whole, declares the Socialist Republic of China. This socialist China is not led by Mao Zedong, but rather Chen Duxiu, who governs rather differently than Mao did, with a rather more open society and emulating Lenin's NEP rather than Stalin's rapid collectivization (which creates some tensions between China and the USSR under Stalin)
Map is around 1940 or so, a little over half a decade since the end of the Second Sino-Japanese War. The central government of China has been seeking to bring warlord territory under central government control, though it has been doing so somewhat gradually, with a sizable portion of territory (the darker China color) remaining under warlord control as of 1940. Also of some note is the Socialist Republic of Korea, liberated in the war with Japan, now a client of sorts of China and pursuing a similar policy path, contrasting considerably to the People's Republic of Korea of OTL. The war in Europe is starting to heat up, pushing Stalin to take a softer tone on the 'deviationist' China, and the pro-peace government that was established via coup in Japan after the fall of Pusan in the war with Japan has itself fallen prey to a militarist coup-the new Japanese government licks its wounds and longs for revenge, though isn't entirely sure how it can actually achieve it
Long story short, Chiang Kai Shek doesn't become leader of the KMT, instead the left wing of the KMT ends up holding power after Sun Yat Sen dies. The United Front continues, and the Communist Party of China grows in influence. Japan still invades Manchuria, but since the Nanjing government isn't busy trying to purge the communists in the encirclement campaigns, Zhang Xueliang isn't left to fight the Japanese alone, and the armies of the central government as well as other warlords (and later the USSR as well) join the fight in Manchuria. After a few years of fighting, Japan is pushed off the mainland and sues for peace, giving China back the territories it had lost since the Treaty of Shimonoseki, giving up control of Korea, and giving Sakhalin and the Kuriles to the USSR. In the aftermath, the Communist Party, now very influential in both the KMT and China as a whole, declares the Socialist Republic of China. This socialist China is not led by Mao Zedong, but rather Chen Duxiu, who governs rather differently than Mao did, with a rather more open society and emulating Lenin's NEP rather than Stalin's rapid collectivization (which creates some tensions between China and the USSR under Stalin)
Map is around 1940 or so, a little over half a decade since the end of the Second Sino-Japanese War. The central government of China has been seeking to bring warlord territory under central government control, though it has been doing so somewhat gradually, with a sizable portion of territory (the darker China color) remaining under warlord control as of 1940. Also of some note is the Socialist Republic of Korea, liberated in the war with Japan, now a client of sorts of China and pursuing a similar policy path, contrasting considerably to the People's Republic of Korea of OTL. The war in Europe is starting to heat up, pushing Stalin to take a softer tone on the 'deviationist' China, and the pro-peace government that was established via coup in Japan after the fall of Pusan in the war with Japan has itself fallen prey to a militarist coup-the new Japanese government licks its wounds and longs for revenge, though isn't entirely sure how it can actually achieve it