I simply want to know IF it's possible, by any way to make it possible to click on the debuff bars(on target, for multidotting for example) so it's easier to take target on that mob?
Or if it's possible with any kind of macro or so.
Thanks
Edit: What I meant was if I click the bars I get target on them.
But another solution would be to mouseover as well, but I can't get it to work. Any ideas?
No it is not possible.
Targeting is only possible on units with UnitIDs and those are typically catered for by your unitframes already, such as target, focus, and bosses.
Having dot-tracking on your boss frames via a unitframe addon would be about the nearest you have to a click-targeting for multi-dotting.