To translate Filters with WPML you need to open translated filter.
At the bottom of the page find Multilingual Content Setup. Choose there Make ‘Product Filter’ translatable
In the Custom fields->br_product_filter choose Copy once
Now click Apply button
When done you will see Language box at the top right corner
Select needed languages in the Translate this Document box as shown on the image
Click Duplicate button when ready. Click pencil icon next to the needed language in the Translations box. You will be redirected to that language page
On the right side find Language box and click Translate independently button
When done change filter name to the one you need and save it.