Hot water side is weak when using the faucet, cold side has no issues. When using the separate sprayer, it only works with the cold but doesn't completely cut off from the faucet. I installed this faucet maybe 5+ years ago and didn't have the issues until recently.

Today I disconnected the hot supply and turned it on into a bucket, plenty of water came out. From the limited searching Ive done, a bad diverter might be the culprit. I've also seen that it is better to replace the faucet than deal with a diverter.

Anyone had experience with this? Here's what I have or at least close enough.

Hot cartridge could be clogged. $15 to replace. Moen might send you one for free. I think they have warranties on their faucets. 2-handle faucets usually avoid all the problems the single-handle ones have. Surprised you're having issues. Is your water terrible?

https://www.homedepot.com/p/MOEN-2-Handle-Replacement-Cartridge-1224/100447982

Edit: don't think it's the diverter. You verified that water supply coming in is good and that you have a problem with both the faucet and the sprayer. That means the problem is somewhere between the supply and the faucet (which pretty much guarantees its's the handle/cartridge).

We got a brand new cartridge shipped to us for free from Moen on a warranty. Pretty easy replacement on the version we have.

call the manufacturer. Tell them you are a loyalist of their brand and have never had an issue before except with this model. They'll likely send you a whole new unit for free

Update
Went through Moen's contact page to describe the issue and they are sending a diverter repair and cartridge for free.

Diverter for the sprayer not fully cutting off water and cartridge for the hot side.