Things on this page are fragmentary and immature notes/thoughts of the author. Please read with your own judgement!
The simplest suggestion is not to waste your time on this right now. There are some old related Vim plugins but are outdated. NeoVim is a better alternative to Vim. Wait to see whether good solutions come out for NeoVim.
Following are some related artilces for typing Chinese in Vim.
http://blog.csdn.net/peterli_xue/article/details/6818212 http://zuyunfei.com/2013//killer-plugin-of-vim-vimim/ 23.04.2017 http://leetschau.github.io/blog/2014//100153/ 06.06.2017 https://sites.google.com/site/vimpl