Hey Yan, thanks for reaching out! 

Do you mind elaborating on what your defining as custom data? 

In the example you provided that classifies risk_score as custom data, Stripe does in fact pull that field. If you look at our Stripe ERD, the risk_score field would be under the Charge table. It does not show up directly in the ERD because risk_score is part of the outcome dictionary (defined by Stripe's API documentation), however it is signified in Fivetran's Stripe ERD that all the key's in the outcome dictionary will show up in the table Charge by the outcome_* field (see picture below).

Let us know if you have additional questions about how to read Stripe's ERD or what is included in the connector!