The forum convention is to mark questions to Toady in (lime) green to allow him to find them when answering at each turn of the month.
Both of the things you ask require magic, which isn't implemented in the artifact release, but is the subject of the next major arc (whose development will start half a year or so after the current release is done, given bug fix/improvement/minor addition releases following the major one). Also note that myth & magic is a large area that probably requires more than one major arc to implement, and it is not certain all of those will be performed in sequence, so some things may be pushed into the unscheduled future.
Binding of demons etc. into vessels are things that are probably intended to be implemented, although when is a different issue. As to effects it probably depends:
- An item specifically made to hold a demon/spirit/... to harness its powers would presumably do so.
- An item designed to contain a powerful creature (to keep it imprisoned) would probably try to nullify any effects, but may fail to do so completely (in which case the effects would probably mainly be negative ones).
- An item designed to contain a creature to allow it to enter a realm where it cannot go unshielded would probably be designed to provide the creature maximum agency.