Hi,
My bad, After verifying, it appears that the capability to be able to configure the display mode of the options per option will be in the next version of HikaShop, not in the current one.
In the mean time, if you want to be able to do it, you would have to create a custom field of the table "product" via the menu Display>Custom fields with the column name "product_option_method" and use the values "check" or "generic" to switch between chekboxes and a dropdown for your options in each product option.