I believe i do underatand the formulation reasonably hold it ... but just ro be sure is there option to wear a weapon but not actualy using it?
Just keep benefit from its enchantment but dont block both your hands.
Generally speaking, no, but there are always exceptions.
Magic items, regardless of what they are, must be equipped properly to provide their benefit - so a shield that provides a passive magic effect of some kind must be actively wielded in one hand to provide its benefit, just as magic boots must be worn on the feet correctly to provide their benefit.
There will be exceptions - in particular, many wondrous items don't really have any particular 'position' they should be worn and can do their thing just by being on your person. A Luck Stone, is an example of this.
Some attunement items will grant their benefit as long as they're on your person and you're attuned to them, but if so, they will say so explicitly. Generally speaking, if an item or object is meant to be worn or wielded in a particular way, then it should be in order to grant any benefit.