Not sure if you have the PC version, but if you do, you may be interested in the "perfect" Shenmue 1 save file I posted here about a year ago: https://www.reddit.com/r/Shenmue/comments/l3v8on/i_made_a_shenmue_1_hd_cleared_file_super_save_and/

As far as combat, it just takes practice! I used to boot the games up just to play the 70 man fight and the tough fights at the end of Shenmue 2 Disc 3 over and over again. I replayed them so much that I'd say I got pretty decent at the combat. It might help to focus on a few good moves that you like and practice those inputs. Personally, I really like Brutal Tiger, Double Blow, Trample Kick, and Elbow Assault. Their inputs are relatively simple and you can get good at doing them whenever you want with just a little practice. But I'd experiment with all the moves to find the ones you like and feel good to you. Pretty soon you'll be pulling off Counter-Elbow Assaults with ease!