What Chinese languages are spoken in South East Asia?
Page 2 of《泰国的西南官话》by 肖自辉 has this little little insert, which is quite nice:


  



Malaysia speaks: Hokkien, Teochew, Cantonese and Hakka.
Singapore speaks: Hokkien, Hakka, Cantonese, Teochew and Hainanese
Indonesia speaks: Hokkien, Hakka, Cantonese and Teochew.
Brunei speaks: Amoy and Hakka.
Philippines speaks: Hokkien and Cantonese.
Vietnam speaks: Cantonese, Teochew, Hakka, Southwestern Mandarin, Hokkien and Hainanese.
Laos speaks: Teochew and Southwestern Mandarin.
Cambodia speaks: Teochew.
Thailand speaks: Teochew, Hakka, Cantonese and Southwestern Mandarin.
Myanmar speaks: Southwestern Mandarin, Hokkien, Cantonese and Hakka.


It's not that surprising to see Cantonese and Min, along with its other branches, getting big representation. Southwestern Mandarin on the other hand is a bit of a shock.