@MCW, Thanks for posting in Q&A. Based on my researching in the following link, I find Google Pixel 8a supports Android Enterprise.
https://androidenterprisepartners.withgoogle.com/device/#!/MCVdxehOnAly1eR3JcNA
Note: Non-Microsoft link, just for the reference.
So I think it supports Android Enterprise Fully managed enrollment.
Hope the above information can help.
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.