If you go to the honda website and pull up the page for the CR-V, you can switch between 2019 and 2020 model years. Another tool I like is that Nissan's website allows you to compare many details about competing vehicles. Try http://compare.nissanusa.com and pick any Nissan vehicle to compare to competitors. Then compare the 2019 CR-V and the 2020 CR-V you're considering and you can see differences side by side on the same computer screen, albeit on Nissan's website, which is obviously not a direct Honda source. I caught at least one mistake relating to the presence of LED brake lights on a 2019 CR-V LX Nissan says it has LED brake lights, but crosschecking that information directly on the Honda site proves the brake lights are not LED for that particular 2019 trim.
Biggest differences off the top of my head is the 2020 LX is going to have the turbo engine like all the higher trims and it's also getting all the safety features that were only available on the EX and higher in 2019. Also, slight changes to the exterior styling and design, new wheel design, and the 12V power source under the radio is getting converted to USB ports. The 12V power source inside the center console is remaining, but the USB ports in the center console I think are likely getting removed, since they're being shifted to under the radio. Not sure about those center console USB ports actually.
Someone also mentioned on this forum that a stop-start feature could be in the works for at least some trim lines of the 2020. Personally, I haven't seen anything on the Honda website to indicate this, but I could have simply missed it. There's also a hybrid coming in 2020, but it probably won't be out until at least February.
Also, there are more LED lights on certain trims for 2020 compared to 2019. I know on the 2019 LX, the only LED lights anywhere on the vehicle are the daytime running lights. Everything else is halogen and older, traditional technology and relatively cheap to replace. LED lights last longer and are arguably more effective, but cost $$$ to replace.
If you like all the gimmicky "infotainment" crap and safety features that blare out loud annoying warnings at you from the dash area, you will enjoy all the craziness of the 2020 models. Personally, I hate all that stuff and I prefer simplicity, so I recently ordered a 2019 LX to avoid all of it. My first Honda.
I nearly bought the 2019 EX, but as luck would have it, the dealer sold the specific vehicle I signed for to someone else before me and it was unavailable. I took a night to sleep on it and decided what to do next, and when I regrouped, I realized the LX was a better fit for my needs and preferences. The only feature I'm giving up that I really, really wanted was the smart entry system. I'm going to have to take the key out of my pocket to unlock the doors. I'm sure this will cause me immeasurable suffering. The rest of the added equipment on the EX was stuff I decided I really don't truly need for one reason or another.