I drive so this is only what I've read.
Disney will transfer you luggage, it could take all day so be prepared for it not to be there until later in the afternoon.
You can uber/lyft or minne van from resort to resort or you can use Disney transport to a park then your resort. If you are all ready for a park day, just leave your luggage with resort #1 to be transferred to resort #2 and bus, walk monorail (depending on where you are staying) to a park, enjoy your day until you get the text your room is ready.
I either call down and check out of resort #1 or go down to the front desk and do it. Just depends on if a call works. Then I drive to resort #2 and check in and leave my luggage with bell services and head to a park. Oh, I do on line check in the night before but even though I've done that I go ahead and go to the front desk when I get there, usually around 7 am or so. Then I head to a park. It depends on if I'm ready to leave the park when I get the room ready text as to whether I head back or not. Most times I don't head back until later in the day.
If you uber/lyft or minnie van directly to the resort, I would suggest taking your luggage with you and leaving it with bell services, that way when you are ready to go to your room you can just stop by and get it.