Archive.org
It gathers digitized documents from several universities, including the Philippine collection held at the University of Michigan
Biblioteca Digital AECID
This is the library of the Spanish Agency for International Cooperation and Development. It hosts a considerable collection of Philippine books and newspapers. They are all in Spanish.
https://bibliotecadigital.aecid.es/bibliodig/es/publicaciones/listar_cabeceras.do
Biblioteca Digital Hispánica de la Biblioteca Nacional de España
They are all in Spanish.
https://hemerotecadigital.bne.es/hd/es/advanced
Biblioteca Digital Memoria de Madrid
It holds digitizations of newspapers from Hemeroteca Municipal de Madrid (you need to scroll down to find the newspapers finder). They come originally from the old “Biblioteca de Ultramar”. They are all in Spanish.
http://www.memoriademadrid.es/buscador.php?accion=VerBuscadorAvanzado
Biblioteca Virtual Miguel de Cervantes
It is embedded in the Portal de Literatura Filipina en Español of that virtual library. It contains newspapers digitized with a BOF project at the University of Antwerp. Those newspapers were held at the library of Colegio seminario de los Agustinos de Valladolid (Spain) and Biblioteca Municipal de Madrid. They are all in Spanish.
https://www.cervantesvirtual.com/portales/literatura_filipina_en_espanol/catalogo_publicaciones/
Biblioteca Virtual de Prensa Histórica
It joins in one online browser and searcher items from different digital libraries in Spain. There are, therefore, quite a few local newspapers, but also a good collection of La vanguardia among other Spanish-speaking newspapers.
https://prensahistorica.mcu.es/es/consulta/busqueda.do
Filipinas Heritage Library
This is the online library of the Filipinas Heritage Library, belonging to the Ayala Museum in Makati. They have a section on newspapers and magazines:
https://opac.filipinaslibrary.org.ph/cgi-bin/koha/opac-shelves.pl?op=view&shelfnumber=319
Online repository of newspapers at the University of the Philippines
Created by the University of the Philippines and the University of Antwerp with a VLIRUOS-TEAM project. It holds newspapers until 1975 in Spanish, English, Tagalog, Chinese, Cebuano, Hiligaynon, etc.
https://repository.mainlib.upd.edu.ph/periodical.php
The Global Press Archive. Southeast Asian newspapers
Great collection of Philippine newspapers
https://gpa.eastview.com/crl/sean/
The Michigan University Press repository
https://quod.lib.umich.edu/p/philamer/
UST Digital Library
This is the digital library of the Universidad de Santo Tomás de Manila, with a significant amount of newspapers and magazines from the Philippines.
https://digilib.ust.edu.ph/browse-by-category.html#hist
The Philippine eLibrary
It is an initiative of the National Philippine Library that joins the funds of this library and the library of the University of the Philippines and some of the items are digitized and online