Hi Liyana,
for the same requirement as yours, I have successfully used in the past the function module
'MATERIAL_SAVE_CONFIGURATION'
that has material and plant in the importing interface while, in the structure E1CUVAL, the characteristic name, description (language-dependent, can anyway be omitted) and characteristic value.can be passed.
If you may need any further info, I will be glad to assist.
Thank you and bye,
Flavio