You can set a maximum number of products that will show on a product page, Follow the below steps.
Step: 1 => Open the ShagunBox app and choose the Cross-Sell app from the side menu.
Step: 2 =>Inside the Maximum number of the product to show(+1) input field, click the drop-down arrow and choose the maximum number of products that you want to set. you can set only 20 maximum and 1 minimum number of products to show, (See screenshot below).
Step: 3 => Now click on the Save Settings button.