https://userapps.support.sap.com/sap/support/knowledge/en/3517230
3517230 - WBS Element field is empty on Asset Accounting reporting Fiori apps | SAP Knowledge Base...
Field "WBS Element" not shown in reporting Fiori apps e.g. "Display Asset Master Worklist" (F1592), "Asset History Sheet" (F1615), "Asset Balances" (F1617)