I'm not sure why by other performers, I actually like to imagine if uncommon languages were on stage at Eurovision haha but that Berryz Kubou cover of Dschinghis Khan is great! France Gall also did a Japanese version of Luxembourg 1965:
Audio ripped from Made in France: France Gall's Baby Pop (2012)
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One I've known about for 10 years+ now is an Afrikaans cover of Azerbaijan 2011 by different singers:
Music video by Monique performing My Hart Het Klaar Besluit. (C) 2013 Sony Music Entertainment Africa (Pty) Ltd - Select Music, a division of Sony Music Ente...
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And sadly there never seems to be enough for my liking in Welsh, which you would think there would at least be UK entries but I did find one of Luxembourg 1972 by Iris Williams though the instrumental was changed:
Welsh cover of Luxembourg 1972.
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