There are 2 options
1. The first option is to export SharePoint data to Excel, then use Excel add-in to import the data to ALM.
2. The second option is to develop additional third party adapters for requirements or defect synchronization using the HP ALM Synchronizer Adapter Software Development Kit: https://hpln.hp.com//page/hp-alm-synchronizer-adapter-software-development-kit-0
HP ALM Synchronizer only synchronizes defect/ requirement data between HP ALM and Rational ClearQuest or Microsoft Team Foundation Server directly, for SharePoint.