If no, is it possible to use WebHDFS API from HDInsight to connect with ADL Gen2?
Unfortunately, ADLS Gen2 does not provides WebHDFS REST APIs.
Azure Data Lake Gen1 has WebHDFS-compatible Rest APIs, where Azure Data Lake Gen2 has Azure Blob Service Rest API.

Reference: ADLS Gen1 Compatibility with Hadoop and ADLS Gen1 vs ADLS Gen2.
Hope this helps.
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