Hello,
There is a bug while importing new Products with features, with
Prestashop Importer - import product from csv, xls, xlsx module. (idk if this happens with other importer modules).
If you import new products with features, they won't be able to be selectable on
Images for product features Module dropdown list and might show an empty list.
So fix by running this query:
UPDATE `ps_feature_value`
SET `custom` = 0;