Change another module state from one module in Vuex

Try it with following parameters as suggested here;

commit('TOGGLE_LOADING', null, { root: true })

If you have namespaced set to true (in Nuxt that's the default when in modules mode), this becomes:

commit('loading/TOGGLE_LOADING', null, { root: true })

you can use action to commit mutation which defined in another module,then you will modify state in another module.

like this:

posts: {
  actions: {
    toggleSavingActions(context) {
      // some actions 
      context.commit("TOGGLE_SAVING"); // defined in loading module
    }
  }
}