Mass Product Actions

Yes, you can change prices per website. Make sure the price has a desired scope in admin > system > configuration > catalog > price tab....

Go to Catalog > Manage Products and make the changes right on the grid.

Please note that it’s not possible to convert simple products to configurable ones and vice versa....

Yes, it will as our Mass Product Actions module works with a database directly. You can edit multiple products, just one product, lots of text, etc....

Yes, there is such an option. You can remove all related products, delete cross-sells or up-sells....

Yes, you can do it via the “Update Attributes” action. Choose it on the product grid and then add or remove products from websites according to your needs:
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This can be achieved by using the “Update Attributes” action. Choose it on the product grid and then modify meta data or any other attribute as you need:
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No, Mass Product Actions extension won't delete associated simple products in this case. “Update Attributes” is a native Magento mass action and we don't change its behavior....

If you need to assign a product to a few categories (like root, parent categories and sub-categories) , you should disable showing categories as tree. Navigate to System > Configuration > Mass Product Actions > Show Categories as Tree > N...

Yes, you can enable it in System > Configuration > Mass Product Actions > Product Linking Algorithms:
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