How can I add a seperate damage dice to my hombrew magic item so that it rolls two separate dice on beyond’s new dice roller?

Got curious for when my paladin reaches lvl 11/2 warlock and gets a permanent 1d8 divine smite all the time. My main weapon is magical gifted by my patron so im looking to see if it’s possible to add the extra dice as a feature so it’s properly displayed and usable in dnd beyonds dice roller feature. I can’t figure out the right combo in the magic item creation page.

Is this hombrew barbarian subclass balanced and fitting for a “thug” barbarian

At level 3 you can roll with the punches. As a reaction when damaged you can generate temporary health = prof +con which will disappear at the end of the round

At level 3 you may be the muscle of the group but sometimes you’re just there to show who you don’t want to be on the bad side of. you and allies with you around have advantage on insight, persuasion, intimidation checks on creatures that have a challenge ratings less then or equal to half your overall level

At level 6: your blows send your foes reeling. after landing a reckless attack the enemy must make a con save dc 8 + str + prof bonus or be stunned till the start of your next turn

At level 10 “is that all you got” spits out bloody tooth you can add your con mod to death saving throws and your allowed one reroll but you must use the new roll and stabilizing you will bring you up to con hp

At level 14 as a reaction when below half hit point choose one creature you can see within 10 ft and they must make a wisdom saving throw (dc= 8+cha+prof) or be frightened of you till they leave the radius or break line of sight where they will remake the saving throw. While raging this affects all enemies within 15 ft