Hi @Tuncel Biyikli,
Thanks for your reply and I understand what you mean. You want the additional lookup columns to show in the edit form, right? This is by design and I'm afraid it is also impossible to show those additional lookup columns using JSON formatting.
As a workaround, click Integrate >> Power Apps >> Customize forms.
Save and publish the form directly in the Power Apps page. Then the additional lookup fields will appear in the edit form.
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