Things give disadvantage to DEX based skills but D&D Beyond seems to forget that Initiative is a DEX based skill. So I'm forced to find ways to give myself disadvantage on initiative.
As far as I am aware, no official published item, spell, feat, or feature grants disadvantage on initiative, and this would be why they haven't implemented it.
Wearing any type of armour while not proficient gives you disadvantage on all strength / dexterity ability checks - saving throws and attack rolls - and that includes initiative because as you pointed out - it is a dexterity ability check - but DNDBeyond doesn't support that yet. So it should be supported because it is an officially published feature.
I can create items/feats to give me advantage but disadvantage is unavailable
Things give disadvantage to DEX based skills but D&D Beyond seems to forget that Initiative is a DEX based skill. So I'm forced to find ways to give myself disadvantage on initiative.
Wearing any type of armour while not proficient gives you disadvantage on all strength / dexterity ability checks - saving throws and attack rolls - and that includes initiative because as you pointed out - it is a dexterity ability check - but DNDBeyond doesn't support that yet. So it should be supported because it is an officially published feature.
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