@Wamebadoc, Thanks for posting in Q&A.
According to your description, I know that you want to change device image in Intune on Linux.
Based on my researching, you can customize the company portal app settings to suit your preferences, change the background color and upload a brand image in Intune > Tenant Administration > Customize. But there is no function to change the device image in Intune.
If you want this function come true, you can submit your feedback to Intune.
Thanks for your kind understanding.
If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.