No, like in Sweden or the Netherlands, the placement into a Foundation means that a legal entity and not a natural person gets the ownership.
Inheritance rules and succession taxes are only applicable to natural persons, so the way Queen Fabiola handles this means she wantsnto safeguard her heritage.
The ' problem' (but perfectly the Queen's own choice) is that she has not generally placed everything at the disposal of the King. A part goes to the Church (most likely the Sisters of Bethlehem which run a monastery at a royal domain in Limbourg), a part goes to a Foundation of the late King, a part goes to the royal couple (hopefully the jewels), etc. So there is a fragmentation but luckily there will be no taxation.
--Previous Message-- : let us hope that this does not mean that : everything must be capitalized (auctioned : off) when she (in hopefully many years from : now) is not here anymore! :