No personal experience but have read that it works. I don’t think any big name builders would do it as a trick for more power, but I understand that the intake ports being a little larger than the head ports is a good thing with the little lip helping to create a touch of turbulence.

Buy a used rec port port online and and install one of each. If your boat goes out and does circles at wot then you'll be certain. Build depending can determinecas to wehether or not it would hurt you. I don't see you losing any noticeable losses. I played around with this years ago only the other way around on the water with real world numbers to show it. No difference in rpm or speed. Baja Rooster kinda explained it. Turbulence, tumbling may help fuel atomization which may in a sense offset the difference. Something I can't explain as to why however only give real results. Would I do it to gain on new builds? No.

You start getting into better flowing ported heads and it can really really take a turn to the worse in a hurry.

I think in the long run you’ll be more happy selling what you’ve got and getting the correct ones. I searched high and low for a used oval rpm airgap and when they popped up they were snatched at $160 o pop. I still had to do a fair amount of hogging out to get the ports even close to being matched but doesn’t take too long with a drum rasp and wd40.