There's a Cosatto swivel one that rear faces up to 18kg and uses top tether.
There's also BabyAuto Dupla isofix which uses top tether even in rear facing mode, up to 18kg. It's not a swivel one. It has the option to harness to 25kg when you move to forward facing and it does all the stages, like Joie Every Stage.
These brands are not top for safety, but there is not a lot of choice in rear facing seats that use tethers rather than a support leg.
Do you know how much your child weighs and their age? - "age 4" is an average so not all of these Group 1 seats will actually last until a child is 4 years old, if they are big for their age.
You do sometimes find with the top tether seats rear facing that the tether is in the way as children get close to the limit of the seat because it passes straight over their head. Also, the fact none of the major brands uses them up to 18kg (for rear facing) always rings alarm bells for me.
The Every Stage is OK, but what you might find annoying is that the seatbelt is in the way to get the child in at all times when it's rear facing. It's also quite bulky in the car taking up a lot of room. And the safety rating for it if you did ever use it forward facing harnessed is not good - Which? gave it a Don't Buy because of the performance in this stage. If you'd only ever use it rear facing and then as a booster, that's not so bad but it still only got "average" results. The seats with support leg do perform quite a bit better. (This is likely to go for the two with top tether I mentioned before as well).
If you're looking at the FX versions of Joie Stages/Every Stage be aware the top tether/isofix fitting is only for the forward facing stages, not the rear facing stage so you're paying for something you won't use for ages yet.
I also always think the Every Stage is a false economy, as it's about £80-100 more expensive than Joie Stages, and even more expensive compared to Joie Tilt, Joie Steadi or Graco Enhance, all of which are similar in terms of rear facing up to 18kg, fitted with seatbelt so no support leg needed. What you get for your extra £80+ is a high backed booster bundled in, but it's a really bulky booster, not great safety rating, heavy/awkward and because it has to fit 12 year olds, it means the headrest is huge and doesn't fit well for younger children using the seat. You are generally better off going for one of the others I mentioned and then buying a booster seat once your child outgrows the rear facing stage. For example, Joie Traver costs about £80 but is much more practical in terms of moving between cars, fits children more closely, is more adjustable to their size, is among the top 10 highest rates booster seats for safety. And if your child is say 1 year old now, if you wait until they are 4 then this seat may be cheaper or there may be something better on the market.