legal requirements are not made by SAP, you have to fulfill such requirements even without running SAP.
your local branches should know about these requirements.
The chambers of commerce and industry are usually very helpful in telling you what requirements you have to fulfill.
For Intrastat SAP provides some contact address in help.sap.com:
https://help.sap.com/erp_hcm_ias_2012_03/helpdata/en/7e/090411884311d294e60000e83dcfd4/content.ht...
