Haxe.vim is a vim plugin for Haxe, forked from vaxe to focus on providing filetype detection, syntax highlighting and indenting for Haxe-related files.
More advanced features are left to LSP client.
Install kLabz/haxe.vim
with your favorite plugin manager.
Apply your usual lsp config, for an example see nvim-lspconfig suggested configuration.
For default configuration and haxe LSP server setup instructions, see nvim-lspconfig server configurations.
require("lspconfig")["haxe_language_server"].setup {}