Hey there. Back around the time of Season 4's Festival of the Lost in 2018, Bungie placed a number of older Emotes for sale on Eververse, for Silver, as a 'Temporal Surge Special'. Most of these were rares and legendaries, but the two featured exotic emotes, 'Mic Drop' and 'Sweeping' were turned into new 'Temporal' versions, with a slightly different glow - the original Sweeping is Blue, the Temporal version is Green. This was, I believe, to keep the originals exclusive for those who earned them originally but also give some exclusivity to those who bought the reprised versions. Yes they are duplicates of a sort, special, and extremely rare duplicates (though likely to get a lot less rare as of this week!). No they are not (to my knowledge) going to be removed.