Adding this after nvm initialisation automatically switches the node version when there is .nvmrc file in the directory

.zshrc

autoload -U add-zsh-hook
load-nvmrc() {
  local node_version="$(nvm version)"
  local nvmrc_path="$(nvm_find_nvmrc)"

  if [ -n "$nvmrc_path" ]; then
    local nvmrc_node_version=$(nvm version "$(cat "${nvmrc_path}")")

    if [ "$nvmrc_node_version" = "N/A" ]; then
      nvm install
    elif [ "$nvmrc_node_version" != "$node_version" ]; then
      nvm use
    fi
  elif [ "$node_version" != "$(nvm version default)" ]; then
# This changes to default when there no nvmrc on every `cd`
#    echo "Reverting to nvm default version"
#    nvm use default
  fi
}
add-zsh-hook chpwd load-nvmrc
load-nvmrc