Native teachers would have better understanding in how to engage the students.
Foreign teachers, depending what the lesson is, might know the subject better. For instance a french teacher teaching french language.
No
A person would normally think in their native language.
The Esperanto words for foreign and native are eksterlanda and denaska.
Antonyms of "native" include minor, unimportant, foreign, alien, outside, secondary, and auxiliary.
native home internal indigenous
One opposite to native is alien.
yes
Domestic
He or she teaches English abroad to students for whom English is not their first language like Asian countries.
A loan word is a word from a foreign language that does not have a direct translation in the native language. Consequently, when the native language wishes to express the idea conveyed by the foreign word, they simply use the foreign word directly.
Artists not native to your country.
foreign