The Sportage back seat was changed in a small – but major – way for 2017; the buckles for 2D & 2P were made rigid, where before all the buckles had been flexible. This change has made the center functionally very narrow in a way that will limit fitting 2 side-by-side and 3-across as now even a narrow booster does not fit in the center, where before it did easily.
The Sportage was redesigned for 2011. The tether anchors now move back up off the floor and onto the back of the vehicle seat. There is no more seat belt overlap as there had been in earlier model years. All of the seat belt buckles are flexible. The shoulder belt for 2C still comes from the roof… yes, this is safe (see here for how to find it and connect it).
The only change to the back seat is that the tether anchors are now on the floor of the cargo area, instead of on the back of the vehicle seat as they had been for 2005-2008.
2005 saw a complete redesign – which brings lower anchors to 2D & 2P, a head restraint for 2C, and a shoulder belt for 2C. The tether anchors are now on the back of the vehicle seat, rather than on the floor of the cargo area as in previous models. All head restraints are adjustable. The shoulder belt for 2C comes from the roof… yes, this is safe (see here for how to find it and connect it). There appears to be some seat belt overlap between 2C and 2P – but at least all the seat buckles are long and flexible.
The only change for 2001 was the addition of 3 tether anchors for the 3 seats in back. Be careful – as there are cargo hooks very close to the tether anchors – and cargo hooks are NOT strong enough to be used as a tether anchor. There are no lower anchors, and 2C continues to have only a lap belt. 
There were 2 door and 4 door models of the Sportage – the images below are of the 4-door model. There are no lower anchors or tether anchors in these vehicles. However, some may have a tether anchor retrofit kit in the glove box – and the 3 weld nuts on the floor behind the seats for each of the 3 tether anchors to be screwed into.
There is only a lap belt in 2C and shoulder belts in 2D & 2P. The head restraints in 2D & 2P are fixed and protrude. There is no head restraint in 2C.
