How to Reference an Image from another Class in Admin Section

I have two apps name app1 and app2 with the following contents in the respective model.

app1 Model

class UserProfile(models.Model):

    user = models.OneToOneField(User, on_delete=models.CASCADE)

    phone = PhoneNumberField(region='NG', max_length=14)

    image = models.ImageField(

        blank=True, default='images/users/icon.png', upload_to='images/users')

app2 Model

class Testimonials(models.Model):

    ACCEPTED = (

        ('True', 'True'),

        ('False', 'False'),

    )

    **name = models.OneToOneField**(

        'user.UserProfile',  on_delete=models.CASCADE)

    job_position = models.CharField(max_length=50)

    content = models.TextField(max_length=130)

    **testimonial_picture = models.OneToOneField**(

        "user.UserProfile", verbose_name=("Testimonial Image"), on_delete=models.CASCADE)

The goal is that I want to automatically populate the testimonial_picture based on the information of the UserProfile, at the admin panel.

I am aware that using related_name in each model field can get me the expected result in the frontend, but how can I get this in the admin section? Thanks in anticipation

See the docs on ModelAdmin.readonly_fields for information and ideas on how to do this.