There are some tools out there to attempt to fix motion blur, but there's no guarantee they'll produce a usable result. One free one is:
https://sourceforge.net/projects/deconvdemo/reviews - no idea how easy it is to use.
If the blur is bad, forget it - nobody can "fix" it. You could upload the pic here and we can render an opinion on fixability.
Both Affinity AND Pixelmator have free trials - fully functioning 30 day trials. Download one or both and see if either can fix the pic. If not, I suspect that you're out of luck.
BTW - Affinity Photo is very easy to use if you've used Photoshop. I'm all for encouraging the Adobe competitors.
Now I'm in a quandary...my 2014 iMac died the other day. Won't start, no way, no how. I suspect either a dead power supply or a dead logic board. I've ordered a new one, as I was thinking of getting something newer soonish anyway, though figured it would be to replace this 2012 Retina MBP with "screen rot" not the iMac! (The anti-glare is delaminating, which they had an extended warranty on until a couple of years ago, BEFORE mine started to go, of course.)
So my quandary revolves around the fact that CS6 apps won't work in Catalina. I either have to get the subscription to Lightroom/PS (GRRRRRRR) or make a really quick transition to Capture One and hope for the best. The MBP, while still very capable, has never been my weapon of choice for photo editing, though it's running Mojave and since LR is already installed, it still works. But it's not a long-term solution either.
I will get the old one diagnosed next week and if it's the power supply, great - will get it fixed as it's probably only about $200. It would buy me some time to decide what to do/make the transition, and then I can sell it or pass it on. But if it's the logic board? Well...maybe not. I've done some looking online, and because mine is a BTO 4Ghz model, guess what? The logic board + labour to install it costs almost as much as just buying a fully-functioning 2014 27" iMac. Unless my repair place has a cheaper source of logic boards, that is.