Multi-Hotbar gives you much more space in your hotbar inventory up to 4 times the item slots. So no matter what your item slot needs, this mod will likely have you covered. If you hit the grave (`) key you can swap between the original hotbar and the multi-hotbar. You will have to adjust the number of available hotbars (up to 4) in the config file.
You can easily jump to the next bar’s item slot by tapping the same number multiple times. So hit any number 1-9 then tap the same number again to jump to the same item slot in the next hotbar. Either that or you can use the scroll wheel to scroll all the way through each hotbar.