Heres a sprinkler/jet thing that i knocked up to suit my bestway 14 foot pool. uses 32mm hose.

Theres 2 versions of the base. One has 2 holes (which are 12mm wide with 172.5mm centres) to suit my pin locations on my pool as seen in pictures, this allows use of origional pins..Ive also included a base which has a centre hole to allow it to suit other pools (then use other holes to cable tie to frame to stop it spinning), theres also some inserts to reduce the pin size if using different bolts/pins. Alternatively, you can also make some new holes to suit your pool in tinkercad , sketch up or something similar.

Edit...Also added a Base with 134.5 centres

ive included 4 nozzles. Theres 68mm and 44mm..The 68mm one is a wider spray but doesnt go as far as the 44mm..The 44mm is a narrower spray but goes further...Id print the 68mm one to start and see how that goes.. I have a decent sandfilter and the included nozzles work fine. If your pumps not got much oomph (paper filter type normally) then use the ones named HIGH PRESSURE (basically same as others tho the nozzle width is narrower at 1mm wide instead of 2mm). If i stick one of them on my filter the water lands in next door but ones garden :-)

Ensure you print them out at a layer height of 0.2 or less. I used PETG so doesnt warp in sunlight etc.

No supports needed, but id use a raft or brim to print the nozzles.

A lot of this was trial and error. The nozzles included here suited my pool and water landed back in the pool.so should suit any from 14ft upwards round..i did mess about playing a bit and found tiny adjustments made a BIG difference to the pressure and often ended up with the flow landing outisde my pool. If you want to have a go at making you own nozzles the the diameter of the nozzle is 31.70mm...if you do make any post a make here and ill give them a go

i run this with a short 32mm hose from the inside of the pool using an adaptor like one in link below, this enables kids just to pop hose on and off inside pool to stop and start it.....tho you can run pump straight to it tho would need to plug hole on return with a pool bung..ive not printed the one in below link so cant vouch for fit etc, but its the first one i came across so should give you an idea..id look round thingyverse and see whats availiable, tho theyre only a few quid on ebay if you dont already have one.. Also try switching between filter and recirculate on sand filter as both have different pressure...

https://www.thingiverse.com/thing:2469017

All comments welcome, and if anyone makes this id be appreciate if you could post a make as only just learning fusion as theres sod all else to do with this lockdown :-) so be nice to see someone else using something i made...Cheers