In general, if a US citizen believes that a Mexican resident has committed a crime, they can contact the appropriate law enforcement agency in Mexico and file a complaint. The Mexican authorities will then investigate the alleged crime and, if they find sufficient evidence, may issue an arrest warrant for the Mexican resident.
If the Mexican resident is arrested, they may be extradited to the United States to face trial. Extradition is a process by which one country agrees to surrender a person accused or convicted of a crime to another country so that they can be tried or punished there. Extradition treaties between the United States and Mexico govern the process for extradition.
It is important to note that the process of filing charges against a Mexican resident can be complex and time-consuming. It is often helpful to consult with an attorney who is familiar with Mexican law and international extradition law if you are considering filing charges against a Mexican resident.