Hi Orestis,
I believe an attribute can be used when adding to the dictionaries with:
https://developer.genesys.cloud/devapps/api-explorer-standalone#post-api-v2-speechandtextanalytics-dictionaryfeedback
"transcriptionEngine": "GenesysExtended",
The transcription engine for the dictionary feedback. Only returned when GenesysExtended feature is enabled.Valid values: Genesys, GenesysExtended.
According to Genesys Cloud Ideas Portal there's also a UI update coming for this.

Regards,
Jeroen
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Jeroen van der Sandt
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