Accessing file share from ETL package in SQL Always-On configuration
It sounds to me like you are suggesting that you require a highly available file share (see https://blogs.technet.microsoft.com/clausjor/2012/06/07/smb-transparent-failover-making-file-shares-continuously-available/). In order to do this you will obviously need Clustered storage (an ip and network name). It would be a little unusual to do this using your Availability Group's Windows Cluster since really that is only in place to provide Quorum and meta-data synchronisation/ mediation of AG Cluster HA objects -and I would personally advice against complicating that deployment -Clusters should be kept as simple and easy to troubleshoot as possible. Instead I would advise to use a remote fileshare - which you can either make highly available via another windows cluster or just use a standalone server (depending upon requirements).