・The merchant name and logo image displayed on the PayPay for Developers screen cannot be changed.
・Our company will change the merchant name and logo image displayed in the transaction history of the staging environment app. Please let us know what you want to change and your Merchant ID.
・The merchant name and logo image displayed in the transaction history of the production environment app can be changed from PayPay for Business.
https://paypay.ne.jp/help-online-merchant/b0026/
https://paypay.ne.jp/help-online-merchant/b0300/