FieldsRaven can create/update metafields of the following types:
single_line_text_field
multi_line_text_field
number_integer
number_decimal
json
On the following resources:
- article
- blog
- collection
- customer
- page
- product
- variant
- shop
Now, your use case of creating a form with fields tied to custom metafields on customer profiles, is a perfect use case for the app, here is an example for collecting custom customer attributes on Shopify and update them on the frontend/storefront.
I hope that helps!