Add support for negative conditions

It's about cities in Romania.

I have a city autocomplete field, a county field (Select2) and Sector (Select2).

Bucharest does not belong to a county, but it's splitted into sectors (1 to 6).

The first field to fill is City.

In normal conditions, county field is required and sector optional.

The logic would be this:

If people fill in "Bucharest", disable County and enable Sector.
AND
Make County optional and Sector required.

If people fill in OTHER but Bucharest, leave county enabled and sector disabled
AND
Make County required and Sector optional.

If I try to make county required by default, when people fill in Bucharest, I the form throws an "Illegal choice" error.
Do I have to start will county and sector optional and make them required depending on the conditionals?

The snippet you asked me for is working but not in my desired way (county and sector still remain optional, regardless of city choice).

I will paste here only that part, not the whole form.

Thanks.

Translation for values in the form are:

Localitate = City
Judet = County
Sector is the same

  layout_destinatar_4:
    '#type': flexbox
    '#align_items': flex-end
    prbe_destinatar_localitate:
      '#type': autocomplete
      '#title': Localitate
      '#flex': '4'
      '#attributes':
        class:
          - form-control
      '#required': true
      '#required_error': 'Trebuie sa alegi o localitate'
      '#autocomplete_items': localitati_romania
      '#autocomplete_match': '2'
      '#autocomplete_match_operator': STARTS_WITH
    prbe_destinatar_judet:
      '#type': select
      '#title': Judet
      '#flex': '2'
      '#options': judete_romania
      '#empty_option': 'Alege un judet'
      '#empty_value': 'Fara judet'
      '#select2': true
      '#states':
        disabled:
          ':input[name="prbe_destinatar_localitate"]':
            value: Bucuresti
        optional:
          ':input[name="prbe_destinatar_localitate"]':
            value: Bucuresti
        required:
          ':input[name="prbe_destinatar_localitate"]':
            value: true
    prbe_destinatar_sector:
      '#type': select
      '#title': Sector
      '#flex': '2'
      '#options':
        1: '1'
        2: '2'
        3: '3'
        4: '4'
        5: '5'
        6: '6'
      '#empty_option': 'Alege sectorul'
      '#empty_value': '-'
      '#select2': true
      '#required_error': 'Trebuie sa completezi sectorul'
      '#states':
        enabled:
          ':input[name="prbe_destinatar_localitate"]':
            value: Bucuresti
        required:
          ':input[name="prbe_destinatar_localitate"]':
            value: Bucuresti
    prbe_destinatar_cp:
      '#type': textfield
      '#title': 'Cod Postal'
      '#autocomplete': 'off'
      '#input_mask': '999999'
      '#flex': '2'
    prbe_destinatar_op:
      '#type': textfield
      '#title': 'Oficiul Postal'
      '#placeholder': 'Ex. Suceava 3'
      '#flex': '2'