replace accents when getting thetvdb series

Question

I'm trying to replace accent mark so I can search properly at my rss:

• TVDB name: Cómo vender drogas online (a toda pastilla)
• RSS title name: Como vender drogas online (a toda pastilla)

and I want to match this so it can be replaced, but isn't working

manipulate:
  - title:
      replace:
        regexp: 'á'
        format: 'a'
  - title:
      replace:
        regexp: 'é'
        format: 'e'
  - title:
      replace:
        regexp: 'í'
        format: 'i'
  - title:
      replace:
        regexp: 'ó'
        format: 'o'
  - title:
      replace:
        regexp: 'ú'
        format: 'u'

My config.yml:

  tv:

    thetvdb_lookup:
      language: es

    configure_series:
      from:
        thetvdb_list:
          username: '{? TvDB.username ?}'
          account_id: '{? TvDB.account_id ?}'
          api_key:  '{? TvDB.api_key ?}'
          strip_dates: yes

    set:
      path: {? path.externaldrive ?}

I want to replace accent mark like this:

á = a

So I can search properly