Mexi.

'mêxih, mêxihtli' est un des noms divins portés par Huitzilopochtli = 'mêxih, mêxihtli' is one of the divine names carried by Huitzilopochtli; also: the name of a person and a divine title; further: 'Mexih Châlchiuhtlatonac', chef légendaire, éponyme des mêxihtin. Il conduisit les Mexihcah d'Aztlân à Cuahuitl îtzintlân. = 'Mexih Châlchiuhtlatonac', legendary chief, eponym of the mêxihtin. He led the Mexihcah from Aztlân to Cuahuit îtzintlân." Wimmer, citing Launey II 206. Finally: '... el sacerdote y señor que los guiada, se llama Meci (Mexi), de donde toda la congregacion tomo la denominacion'. = the priest and lord who guided [the migrants] is called Meci (Mexi), from where all the congregation took the denomination. Citing Duran. Historia de laS Indias de Nueva España 1951 I 19. Cf. Codice Ramirez. Relacion del origen de los indios. 1944,24. Cf. Cronica Mexicayotl 1949,14-16.
https://gdn.iib.unam.mx/diccionario/mexi/54637

oiuhqui yn ynic nahualpolliuhque ynic chimaltlacuecuepaltica polliuhque yn azteca mexitin chichimeca huehuetque ynic quiytztinenque ynic quimaceuhque tlalli = Thus it was that the Azteca Mexitin Chichimeca ancestors were ambushed, defeated by trickery, through the reversing of the shields when they were attending to the obtaining of land. (central Mexico, early seventeenth century)
Codex Chimalpahin: Society and Politics in Mexico Tenochtitlan, Tlatelolco, Culhuacan, and Other Nahuatl Altepetl in Central Mexico; The Nahuatl and Spanish Annals and Accounts Collected and Recorded by don Domingo de San Antón Muñón Chimalpahin Quauhtlehuanitzin, eds. and transl. Arthur J. O. Anderson and Susan Schroeder (Norman: University of Oklahoma Press, 1997), vol. 2, 76–77.

Auh yn ompa yn inchan ytocayocan aztlan. yehica yn intoca azteca yhuā yn ompa yn inchan ynic ontlamantli ytocayocan chicomoztoc. auh ynin azteca yntoca azteca yhuan yntoca mexitin. auh yn axcan ça mellahuac yn mitohua yn intoca Mexica. Auh ca quin nica quicuitacico yn intoca tenochca = Their home was the place named Aztlan; hence their name is Azteca. And the second name of their home was Chicomoztoc. And their names were Azteca and also Mexitin. But now their name is really said to [be] only Mexica. And later they arrived here taking as their name Tenochca (central Mexico, early seventeenth century)
Codex Chimalpahin: Society and Politics in Mexico Tenochtitlan, Tlatelolco, Culhuacan, and Other Nahuatl Altepetl in Central Mexico; The Nahuatl and Spanish Annals and Accounts Collected and Recorded by don Domingo de San Antón Muñón Chimalpahin Quauhtlehuanitzin, eds. and transl. Arthur J. O. Anderson and Susan Schroeder (Norman: University of Oklahoma Press, 1997), vol. 1, 68–69.

Nican mitohua motenehua ynquenin oacico, ocallaquico ynhuehuetque inmitohua Motenehua Teochichieca Aztlan tlaca Mexitin Chicomoztoca. = Dícese,nómbrase aquí como llegaron y penetraron los ancianos llamados, nombrados teochichimecas, gentes de Aztlan, mexicanos chicomoztoquenses... [Aquí se dice, se nombra (el) cómo vinieron a llegar, vinieron a entrar los ancianos que se dice, se nombra los "teochichimecas", gente de Aztlan, mexicanos chicomoztoquenses...] (centra de Mexico, s. XVII)
Fernando Alvarado Tezozomoc, Crónica mexicayotl; traducción directa del náhuatl por Adrián León (México: Universidad Nacional Autónoma de México, 1998), 3.