your way is not bad,, simple and easy way.
(basically,, of course the product for genesis, need to fit other genesis morph,but
sometimes or often may need adjust the shape for character morph I think,,)
then I think,, if you move the hip bone,, (and the figure has another bones too)
the figure can not move same as you change hip transltaiton parameter,,
because only hip bone may move but other bone of the figure (gun or holster) try to
stick to the bone of genesis still, so the movements are restricted,,.
you can check easy,, how the figures (of your items) node arrange,,and how it move.
by scene tab, and bone visiblity setting.
select the item root, in scene tab, then go to parameter tab,
and change setting of bone visiblity in paramete tab display mode. (need to change opacity too,,)
after that,, you can check which bone is best when you adjust the positon.
there would be more suitable bone to adjust the positon about holster or gun figure,,,.
(in mycase,, there is sword ghost bone,, lucky to me,,)
and ,,,,actually,, you can set the figure not “fit to” just “parented” like a prop.
I often just parented the these type figure,, (gun or swoard or sheeld or holster ,,, hair,,too,, )
to geensis node of hand, or plevis, arm, head,, etc.
because it can easily move and adjust positon for many pozing. and it can move with genesis node,.
but if parented , the figure can not auto follow morph of genesis, so you may need manually adjustment by scale, or
the figure morphs if they have,,,( I am not expert at all,, but hope,, if it may help some)
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