There is no safe way. Google and Easypaisa have both removed old versions from official channels because they are unsafe.
Modern versions of the Easypaisa app require recent Android operating systems (typically Android 7.0 or higher) to function. Users with older smartphones running Android 5.0 (Lollipop) or Android 6.0 (Marshmallow) find themselves locked out of the official Google Play Store updates. Version 2.6.1 is often sought because its system requirements match legacy hardware. 2. Device Performance and Storage Limits Easypaisa Old Version 2.6.1 Download
Older versions do not receive security patches. This leaves them exposed to newer malware threats. There is no safe way
Because Google Play Store only hosts the most recent version of apps, you must download version 2.6.1 via a third-party APK website. Follow these steps to install it safely: Step 1: Enable Unknown Sources Users with older smartphones running Android 5