Im not 100% sure if its a bug or not, but I think that very likely it is.
Sure, it might be intended by the developers that when our characters stop moving, they make a brief animation as if they were holding a phaser pistol in their hands (even if their weapons were holstered) but if it is, it sounds like a bad idea to me and while not a huge-game breaking issue, I find it very irritating.
WHEN THE GAME WAS RELEASED, UP UNTIL the ground combat update, (if memorys serves) I believe there was NO SUCH ISSUE, so it makes me think that the ''stopping animation bug'' must be an artifact from that (now old) Season xx that updated the ground combat mechanics.
Please fix it, as it has been around long enough already. I mean, sure, we do get new lockboxes all the time and im certain your busy with that stuff, but I think we (finally) deserve the fix to this animation thingy after so many months.