Car misses while moving

I have 2 tdi beetles 1 is a 98 the other an 01 I've noticed both cars seem to have a substantial miss when I'm coming to a stop but as soon as my wheels stop rolling the miss stops until I start to stop again it seems like it's electrical

Could this be a low IQ stumble? Either one a manual trans? If any have a manual trans then what happens if you're running along and you just push in the clutch and let the RPMs drop?

They're both standards I just did a five speed swap on one if you just push in clutch and coast to a stop that's when they do it

Yeah, really sounds like an IQ issue. Need VCDS (or equiv) to check and set IQ (bump it up). If you just put a 5spd into a car that had an automatic it'll for sure need some adjusting (larger IP than in manual transmission cars [stock] and smaller nozzles- there will be a slight mismatch going on here that will require a bit of tweaking). Regardless, need to check IQ. I'd also think it a good idea to check timing.

Is it bad? A slow down stumble is actually normal on these cars. I've logged the idle and fuel on mine, the injected quantity drops to zero when you take your foot off the accelerator. A diesel purge might help, if you never done that. Or injectors getting worn, weak pump, dirty/clogged filters maybe.