Hello Diego,
Yes, the Out of Stock status can be also changed in bulk using the Mass Product Changer > Advanced Modifier
Diego Morales,
You can filter In-stock products using the header column filter:
Then select all (Ctrl+A) and use Mass Product Changer in order to apply the mass changes.
Also, if you would like to deny orders for products In-stock, you may disable "Available for order" option for them: