Homekit custom sensor

I wanna be able to add custom sensor can this be done?

Example my washer to display minutes left of the cycle like 22min. I can now make it a temp but its silly to say washer 55 celsius.

Example two display a string ie message like Tesla battery 50 %.

found this on apple should be possible?

“For other characteristic types, the corresponding value might be a plain number, a string, or Boolean, or a blob of data with encoding specific to that type.”
https://developer.apple.com/documentation/homekit/hmcharacteristic/characteristic_types

"Information
let HMServiceTypeLabel: String
A label namespace service used when an accessory supports multiple services of the same type.

let HMServiceTypeAccessoryInformation: String
An accessory information service."

https://developer.apple.com/documentation/homekit/hmservice/accessory_service_types?fbclid=IwAR2ytE2WZBLuhLPBDBuSPH1fYtufmmPJ8ubdXoKgvo1x-H3gS8fgS2ougv0

“Uncategorized
let HMAccessoryCategoryTypeOther: String
An uncategorized accessory.”

https://developer.apple.com/documentation/homekit/hmaccessorycategory/accessory_category_types?fbclid=IwAR07_7EtQRqqDHAdi_or5BrPzxuY3k5vWdIt7p0CXVlJA7GlBxPcamLSLxo