It is important to differentiate between the political systems and election processes in China and Mexico, as they have distinct characteristics.
China:
China is a one-party socialist state governed by the Communist Party of China (CPC). The political system in China does not allow for multiparty elections, and the government maintains strict control over the electoral process. In this context, it is widely considered that elections in China are not fair, as they lack key elements of a democratic electoral process, such as political pluralism, genuine opposition, and protection of individual freedoms.
Mexico:
Mexico has a multiparty system and a democratic government. Over the past few decades, Mexico has undergone significant political reforms to improve its electoral process. The National Electoral Institute (INE), an autonomous public organization, is responsible for organizing federal elections in Mexico. Despite these efforts, there have been concerns about election fairness in Mexico, including allegations of vote-buying, intimidation, and violence, especially at the local level. However, the overall electoral process in Mexico is generally considered to be more democratic and transparent compared to China.