Thank you for your reply! I actually never save to iCould or Adobe Cloud and always save locally or to external hard drives. I just saw there was a new Photoshop 2020 update since my initial post here, and I updated to it today however Save for Web (Legacy) still crashes when trying to save animated GIF files.
I have had the opportunity to test Photoshop 2020 Save for Web (Legacy) on a temp loner MacBook Pro laptop running Apple's Mojave OS and had no crashes. So with my limited testing it seems to be an issue with Photoshop on Catalina. I hope there's a solve for this soon.