The ArcGIS Server Feature Service Writer will be available soon for the 2023 beta version, however there is no option to add atachment as it is done with arcgis pro. The attachments known to be a useful way of providing additional info in the form of a specific file.
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Related idea:
https://docs.safe.com/fme/2024.1/html/FME-Form-Documentation/FME-ReadersWriters/arcgisfeatures/format-attributes.htm