TLDR: set type=“string” and field_type=“html”
I think have a solution here, I just tested it on my own HS. First I read a rich text (html) property to see what the values were set to, then I tried to imitate those values in the call to create the property. I believe the import part is to set type=“string” and field_type=“html” but I’m not sure whether you’re allowed to have html be form properties or other things like that. So here is the full return from my api get call in case it’s helpful.
'results': [{'archived': False,
'archived_at': None,
'calculated': False,
'calculation_formula': None,
'created_at': datetime.datetime(2024, 4, 26, 13, 55, 25, 153000, tzinfo=tzutc()),
'created_user_id': 'XXXXXXXXXX',
'description': '',
'display_order': -1,
'external_options': False,
'field_type': 'html',
'form_field': False,
'group_name': 'deal_properties',
'has_unique_value': False,
'hidden': False,
'hubspot_defined': None,
'label': 'XXXXXXXXXXX',
'modification_metadata': {'archivable': True,
'read_only_definition': False,
'read_only_options': None,
'read_only_value': False},
'name': 'XXXXXXXXXXXXX',
'options': [],
'referenced_object_type': None,
'show_currency_symbol': False,
'type': 'string',
'updated_at': datetime.datetime(2024, 4, 26, 13, 55, 25, 153000, tzinfo=tzutc()),
'updated_user_id': 'XXXXXXXXXXXXX'}]