It depends on what mod(s) are in both of the modpacks, and if the two modpacks are from the same MC version. I checked, and Create Live 4 is on Minecraft 1.19.2 while ATM9 is on 1.20.2. So no, probably not. At best, you could transfer your save to a vanilla world, load it in 1.19.2, and then load it in vanilla 1.20.2 to ensure no bugs occur. Then put it into the saves folder for ATM9. TLDR: No, unless they are on the same MC version and have some of the same mods.