A number of rural migrant workers in China DO go to Vietnam to work[0], though this has been increasingly cracked down on by the Vietnamese government[1]. On a similar note, the Belt and Roads Initiative itself essentially acted as a jobs placement program to alleviate labor issues after the 2015-16 Stock Market crash in China [TODO: Find page numbers from notes]

[0] - https://data.vietnam.opendevelopmentmekong.net/dataset/fefed...

[1] - https://www.rfa.org/english/news/china/workers-1029202011165...