It's been suggested in the Zendesk feature requests forum, but not sure if that forum is still being used by the current D&D Beyond team...

Quoting "Haravikk", who explains it very well : 

"Currently on the character sheet it's possible to customise weapons in order to specify or boost the hit roll modifier, and to add bonus damage, as well as make a weapon adamantine or silvered, and to add notes.

However there are some customisation options that we are lacking, which also cannot be done using homebrew:

• Range: It isn't currently possible to customise range, but this would be very useful to be able to do as a range note is easily missed, and clutters the interface.
• Damage Die: While we can add a bonus/penalty to damage rolls, we can't change the base die used by a weapon, it would be good to see an option to set the type and number of die rolled for a weapon's attack. Versatile weapons should provide two options for setting each value.
• Damage Type: Allow us to choose a weapon's base damage type, this would be handy for weapons that are otherwise close to what a player needs except for the type.
• Properties: While we can add notes that can give the appearance of adding weapon properties such as Reach, we have no way to remove them.