Editing or changing an IMEI to a number other than the one originally assigned to the device is illegal in many jurisdictions. Always use the original IMEI found on your device's box or under the battery.
Connect your device and use the "Read from NVRAM" function. You will need to select the appropriate APDB file for your chipset to correctly map the data fields. mtk nvram editor
: Used primarily for writing serial numbers, IMEIs, and MAC addresses in a production or repair environment. SP Flash Tool Editing or changing an IMEI to a number