No, if the Solvency II amount is negative it is not an asset but a liability. List of assets need to reflect the assets reported in the balance sheet were no netting should be considered. The only exception is bank overdrafts. As deposits are reported by currency/bank it might happen that this amount is negative if both legal right of offset and demonstrable intention to settle net exist.

Please see also instructions for Cash and cash equivalents in the balance-sheet: “Bank accounts shall not be netted off, thus only positive accounts shall be recognised in this item and bank overdrafts shown within liabilities unless where both legal right of offset and demonstrable intention to settle net exist”.