How to Populate image field via a URL in another field

Matt_UHB You cannot do it using SharePoint out of the box capabilities as SharePoint Image columns only supports adding images from your computer.

You will have to upload those images to your SharePoint site and then use Power Automate or PowerShell to update image fields as shown in below articles:

1. Add/Update image columns in SharePoint/Microsoft Lists using PnP PowerShell 
2. Update image in SharePoint/Microsoft Lists Image columns using Power Automate 

OR you can simply use the JSON column formatting on your hyperlink column to turn it to show the image in SharePoint list. Use JSON like: 

{
  "$schema": "https://developer.microsoft.com/json-schemas/sp/v2/column-formatting.schema.json",
  "elmType": "img",
  "style": {
    "background-color": "none",
    "width": "100px",
    "height": "100px"
  },
  "attributes": {
    "src": "@currentField"
  }
}

Find steps to add JSON formatting at: SharePoint JSON column formatting 

Please click Mark as Best Response & Like if my post helped you to solve your issue. This will help others to find the correct solution easily. It also closes the item. If the post was useful in other ways, please consider giving it Like.