Whenever discussion of the late Qing is widespread on this forum, a single poster or more will often steer the discussion to modernization attempts made under the Self-Strengthening Movement and the Hundred Days Reforms, as well the intentions of Prince Gong; while this sort of wishful thinking is usually accompanied by acknowledgement of the radical shifts in Chinese policy and mindset that would have been required for this process to even begin properly, as well as the factor of western ethnic groups hostile to the Qing and determined to take advantage of their weakness. What I've never heard in coversation is how an attempt to Westernize the the traditional Chinese monarchy would have led to clash between liberal constutionalism and the concept of divine mandate. The Mandate of Heaven sound downright contradictory when measured by the standards of European political thought: it preaches a sanctity of the emperor similar to the divine right of kings, but at the same time enshrines the duty of revolt within its very core, something more obviously republican and therefore less tolerable under under the dynasties of the west. Factoring all this in, the only way fro China to remain true to its dynastic roots while implementing modern-style government would be if one looked to liberal Britain for a solution, but the even the following is sketchy due to cultural differences: the Revolution of 1688 was the climax of a long line of Parliamentary victories against royal absolutism, which depending on one's historiography can be traced back to the Tudors and early Stuarts or as far back as the Barons' Wars , each establishing the rising supremacy of the estates over undiluted royal decree. By the eighteenth century, it was clear that while the monarch held primacy over the English and Scottish Churches as well as general policy, the power of day to day legislation was in the hands of the two houses. An attempt to implement something similar in China--where a parliamentary body could depose an uncooperative sovereign at will, or even dynasty as a whole--would have thrown up legal crises at what was probable grounds for removing the former or the latter, as well as created multiple claimants from rival families, up and coming politicians and disgraced members of the royal family. This alone would set up multiple constitutional issues, ecspecially when Parliament tries to get rid of a problematic monarch without the tradition al "sign of heaven"--natural disasters, civil unrest, bad harvests, etc.--and would require a complete overhaul of view the Chinese traditionally viewed their son of heaven, with him being reduced from hegemon over the whole civilzed world to just another sovereign subject to international and parliamentary law. The only way any of this could begin to happen was if two factors happened to be in place. First, the Qing needed to reconnect with the people of China by setting aside the Manchu cultural dominance of the imperial court and striving for a doctrine of unity similar to the OTL Republic's five races under one flag, and second, the idea of the emperor would have to be radically altered to fit in wit the models present in Korea and Japan, where instead of heavenly governors appointed at will the concept was instead that of a ceremonial family hovering over the beauracracies of state and presiding oonly over nation states.
TLDR: Any attempt by Qing China to constitutionalize in the model of Japan or western Europe would ultimately fail due to the fact that the cyclical nature of the Chinese monarchy could not be made compatible with the demands of liberalism and legalized transitions of power, and to over come this the imperial court would have had to make massive changes to how it consolidated power as well as how it propogated the idea of the son of heaven,
TLDR: Any attempt by Qing China to constitutionalize in the model of Japan or western Europe would ultimately fail due to the fact that the cyclical nature of the Chinese monarchy could not be made compatible with the demands of liberalism and legalized transitions of power, and to over come this the imperial court would have had to make massive changes to how it consolidated power as well as how it propogated the idea of the son of heaven,