Naaa, I get big boxes of vintage linens at auction all the time. Pull out the good stuff first and list separate (name brand jackets, sweaters, fancy items), then list the rest in groups of 3 or 5 or whatever. If they are smaller sized items, you could probably list 8 or 10 in a lot. Sort of put like items together, all long sleeved tops in same size.
ebid requires clothes be clean, so if smudged, soak overnight in detergent with bleach alternative or enzyme cleaner like oxyclean. Don't mention word "dirty" in listing, that is a forbidden word on ebid. Make sure you describe any faults such as seams undone or whatever too, ok to sell them, just tell buyers that they need a few stitches.
Those boxes are worth a tidy little sum, might as well sell em!