Smelly water in between washer barrels
Possible problems include:


pump bad (may be eating a sock or something)
control board bad
drain line has an issue
possibly a transmission issue if the spin isn't working


All, or virtually all, the water should pump out. In the short term, put in a cup of bleach and run a short cold cycle (no clothes or soap) to kill off the smellies.

I had a similar issue at one point and was pretty sure the pump was bad, but I wanted to remove it before ordering a replacement - when I did, I found an obstruction (in my case, some silicone rubber from a prior tub repair job, which I had done "inside and out" to "make sure" - the inside part peeled off, the outside part continued to work) lodged in the impeller. Removed the obstruction, reinstalled the pump, washer worked fine again. Unless it is eating an escaped sock, you probably won't get that lucky.