It depends on the grinder. Frozen beans at -19°C when ground through an EK, come out of the grinder between ~15°C to ~20°C - with a far higher ratio of fines to boulders than you would if ground at a higher temp. So we've got this neverending "pull one end of the string, it pulls several others in a different direction".
Isolated, I'd say the lower grinds temperature would have an effect on flavour, potentially negative if all other variables were held constant. But they're not, and the lower grinds temp is balanced out then pushed into the positive by the higher amount of fines, resulting in a net gain in flavour.
What can mess this up however is poor distribution. Those same "strings" also pull in the direction of creating an environment for clumping. Static and other environmental conditions can conspire to create clumps out of all those fines, creating barriers to the flow of water and espresso out of the basket.
So to benefit from grinding frozen, therefore creating more fines, which will mitigate the slightly lower grinds temp, you need to ensure you've distributed really well in the basket. For me, I grind into a pre-weighed cup, adjust the dose if needed, then pour the dose into the basket using a jam funnel, and from there I use a small whisk to break the grinds up if any clumps have formed. Palm tap, tamp, and pull : )
Then just make sure you've lowered your pump pressure, you're using a controlled tamp force, around 58.3mm tamp circumference at least, your grinder is cleaned and aligned, you've built your own water — and of course you're freezing beans ; )