Rodger Etz composed on 2019-10-03 19:11 (UTC):
So it seems Alan and myself have got some rare dependency condition.
Still need to find out what exactly triggers it and how to solve it.
Will open a bug tomorrow, if nobody beats me to it.
Likely you can work around the problem via exclude= in dnf.conf for the checksum problem packages to get upgraded to f31, and deal with those skipped packages later.