No. ‘Haneul’ is the pure Korean word which stands for ‘sky’. ‘chun’ is Hanja that Korea imported.

I`m afraid that your understanding of Asian language is quite short - 電 is the least character that was made by Japan, cause it was one of the initial symbols that were made by Chinese - you can find the character from I ching, the oldest of the Chinese classics, which was written 2500 years ago.

It`s quite common between those three countries - for instance, ‘sky’(Tien in Chineese) is pronounced ‘Chun’ in Korean, ‘Ten’ in Japaneese.

“It seems more likely that Korea took their pronunciation from the Japanese version though”