If I understand you correctly, here's a
tutorial on how to make accessories wearable at all times. You have to do it on all the accessories, though.
Most accessories are cloned from the maxis ones, which are not wearable with all types of clothing. Not everyone bothers to fix this. Not sure if you mean body types as in fat/fit or as in the bodybuilder meshes or such, but as ar as I know, accessories should be wearable with all body types. However, if the accessories are small, there might be a chance that they don't show up on the sim if the bodymesh covers it.