A WooCommerce variable product is a standard product type which allows you to offer a group of variations (different sizes, colors, etc) in a product to your customer. This simply means that it shows a wider array of attributes which your customers can choose from.
This maximum number of variants per product are all governed by the code in your WooCommerce site and your web server. This is not managed in Hyperspace or through your WooCommerce integration.
There are numerous articles online about clients having issues syncing products with 30, 50 and even 100 variants. The solution for all of them boils down to making modifications to their WooCommerce code or changing settings in their web server.
If you used to sync products with 100 variants and now you are limited to less, then it is likely that your web host provider has modified a settings on your server or new code was added to your WooCommerce site due to an update.
It is advisable to use your own WooCommerce developer since WooCommerce updates could revert the code back to default in the future. If you do not have a WooCommerce developer that you work with on a regular basis, Hyperspace can refer one to you.
1. Increasing the number of variants per product in WooCommerce may affect your website's speed.
2. Version and plugin updates to WooCommerce may revert back any changes that you make to your WooCommerce core code.
Here are a few examples articles you can send to your WooCommerce developer.
Here is a good article to forward to your web developer.
Increasing the threshold to prevent the AJAX variation from hitting its limit in WooCommerce -https://gist.github.com/claudiosanches/6f91ad228c2176b986b2
Sometimes the change is not as simple as editing code in WordPress. You may need to reach out to your web host provider and ask them to increase the your I/O settings.