Since 'øyeblikk' (a glance) refers to something that only takes a very short time, why not accept something like: 'It only takes an instant.' A moment is a considerably longer period of time, up to a couple of minutes (see: https://en.wikipedia.org/wiki/Moment_(time)). I believe 'It (only) takes a second' usually means anything from one second to half a minute, usually closer to the latter than the former, but I would also find that it corresponds closer to the original meaning than 'moment'.
Quite agree , " just a moment " , is another example to express what you mean
It accepts "it takes a moment" as well as "it takes just a moment". The former means that something takes a little while, whereas the latter mean it takes a very short amount of time. The first sentence should not be accepted
I would say "Øyeblikk" is shorter than "Stund". "Øyeblikk" is just a really short time, while "Stund" is a little longer moment.
What is actual meaning of this sentence? "It takes some time (longer period)" or "It takes only a really short period of time "
Only a really short period of time. Literally "Det tar et øyeblikk" means "It takes an eye glance (øye=eye and blikk=glance). If you want to say "It takes some time", it works perfectly fine to translate it almost directly to "Det tar litt tid".
Hmm. "just a minute" =/= "a moment"? Or is it because minutes and seconds are measures, and a "moment" is not? I'm a little mystified....