I probably should've posted this sooner, but better late than never.

When you Shark an MR1 monster for maxxed stats, save and deactivate the system, then remove the GS and resume play. Go to the ranch and train the monster in every stat once, and the ridiculously high stat numbers will go down to normal 999 stats.

Once this is taken care of, pop in MR2 and attempt to slate the monster. You will find that it's maxxed stats are completely normal, rather than displaying an overload of 9s spanning the width of the screen. The slated monster will be born with perfectly normal slated stats.

There is some sort of exception though, Fenrick's site has a save where there are a bunch of MR1 babies in the MR1 freezer. If you slate those, they are born with stats that change slightly each time, but are like: 3,3,3,3,3,3 or 4,4,4,4,4,4. I do not know if the save is from the week of sharking, and they normalize if you just let a week pass in the mr1 save or not.

If anyone is working on this, there is a fairly simple way to deal with this, but it assumes you are actually willing to put some effort in on the sharking (i.e., either plan ahead or have the shark handy).

I posted a pretty detailed description in a new thread (I've been hitting closed discussions, and I forgot to check to see if this one was open):

Monster Rancher Metropolis: Monster Rancher 2 Archive (PSOne): Miscellaneous Q&A (Post New Questions Here): Sharking for the Perfectionist