What are the only two African nations that were never colonized by the Europeans?

Only Ethiopia and Liberia were African nations not colonized by Europeans.

Their location, economic viability, and unity helped Ethiopia and Liberia avoid colonization.

https://www.thoughtco.com/countries-in-africa-considered-never-colonized-43742

I'm not sure if Ethiopia can be considered... It was an Italian colony just prior to World War II (1936)

Italy was one of the European countries with colonies in Africa during the modern period. Lasting from 1890 to 1941, Italian colonialism in Africa included the present day countries of Libya, Ethiopia, Eritrea, and Somalia. Italian colonialism in Africa came to an end with the death of the Italian leader Benito Mussolini, the collapse of the Fascist regime, and the defeat of Italy in World War II. Half a century of Italian colonialism had long-term effects on attitudes towards race and racism in both Italy and its colonies.

Italian East Africa, Italian Africa Orientale Italiana, group of Italian possessions in eastern Africa in the period 1936-41. It comprised Ethiopia (annexed by Italy on May 9, 1936, and proclaimed a part of Italian East Africa June 1) together with the Italian colonies of Eritrea and Italian Somaliland (now part of Somalia). Italy's king, Victor Emmanuel III, was named emperor. British forces overran the area between January and November 1941.

Food for thought...

Some scholars argue, however, that Liberia’s 23-year period of American domination until independence in 1847 qualifies it to be regarded as a colony.

Ethiopia is considered “never colonized” by some scholars, despite Italy’s occupation from 1936–1941 because that did not result in a lasting colonial administration.

https://www.encyclopedia.com/social-sciences/encyclopedias-almanacs-transcripts-and-maps/africa-italian-colonies

https://www.britannica.com/place/Italian-East-Africa

https://www.historicalafrica.org/countries-in-africa-considered-never-colonized/

It is my understanding that what is today's Eritrea used to be part of Ethiopia. This is the part that the Italians controlled. The Italians never controlled the entire country from what I read and the Ethiopian government was able to be maintained without having to yield to the Italians.

As for Liberia, they did not have any resources the Europeans wanted and while the US may have had control for a short time, the US is not part of Europe and the US was not looking to exploit Liberia but rather resettle former slaves.