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transforms=HashEmail
transforms.HashEmail.type=org.apache.kafka.connect.transforms.Hash$Value
transforms.HashEmail.field.name=email
transforms.HashEmail.function=sha1

Based on feedback from Gunnar Morling (https://debezium.io/documentation/reference/connectors/mysql#mysql-property-column-mask-hash) I think that this should also support 
1) an optional salt, which would be set via transforms.HashEmail.salt
2) a comma separated list of fields where a period is used to denote nested fields
Given these suggestions

transforms=HashFields
transforms.HashFields.type=org.apache.kafka.connect.transforms.Hash$Value
transforms.HashFields.field.name=user.email,user.ssn,contact
transforms.HashFields.function=sha1
transforms.HashFields.salt=F4xJK03Ab

Compatibility, Deprecation, and Migration Plan

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