"w" in Japanese is not an onomatopoeia but an abbreviation (for 笑い "warai" laugh) as same as in English "lol". There is an actual laughter onomatopoeia in Japan

"w" in Japanese is not an onomatopoeia but an abbreviation (for 笑い "warai" laugh) as same as in English "lol". There is an actual laughter onomatopoeia in Japanese too, it's "fu(fu)" or "a(ha)".