We need to know where geographically you are located, whether the pavers are in sun or shade and a photo of the area in question would be very helpful as well.

Fill the space with tiny stones mixed with cement it waill fill the gap and deter weeds. Any ground cover will grow and need contiual cutting. So something like this is attractive too.

I'm in zone 5 and it gets at least 6 hours of sun a day.

I have used a creeping thyme to fill in around concrete slabs. It's pretty. Now I have moss (I didn't put it there) and it looks nice too.