The terminal_transparent option doesn't seem to work for me.

[cm-s]

This is the contents of my .vimrc.

filetype plugin indent on
call plug#begin('~/.vim/vim-plugins')
Plug 'KeitaNakamura/neodark.vim'
Plug 'https://github.com/joshdick/onedark.vim'
call plug#end()

colorscheme neodark
let g:neodark#terminal_transparent = 1
let g:neodark#use_256color = 1

And this is my background when editing.

[KeitaNakamura]

Hi. Could you try to put those settings before colorscheme neodark?

let g:neodark#terminal_transparent = 1
let g:neodark#use_256color = 1
colorscheme neodark

[cm-s]

Very nice, it worked. :) Thanks, and great looking colorscheme!