solidworks 2018: export large assemblies

[rg9_90]

Good morning
I need to export a set from 770.000 kb with solidworks 2018 to pass it to fusion of inventor.
what is the best and lighter export format?
iges, step and parasolid are too heavy for those who have to handle them only for aesthetic use.

 

[MassiVonWeizen]

if the starting aid and from 770mb there is no format that reduces the weight also because while the axieme loads the data from external files (parts and/or sub-assiems) a single file must include everything and therefore would weigh more.
if you only need for aesthetic use saves as part specifying to use only external surfaces