This can be done using the PRTG API
Fitst create a list of all your PING sensors using the table.xml API call
/api/table.xml?content=sensors&output=xml&columns=objid,device,sensor&filter_type=ping
This will create a xlm result looking something like this:
<item>
<objid>2186</objid>
<device>Cisco 1800</device>
<sensor>Ping</sensor>
</item>
<item>
<objid>2188</objid>
<device>Alarm</device>
<sensor>Ping</sensor>
</item>
<item>
<objid>2190</objid>
<device>CCTV</device>
<sensor>Ping</sensor>
</item>
<item>
<objid>2192</objid>
<device>Cisco 2900</device>
<sensor>Ping</sensor>
</item>
You now have the objectID's of all your PING sensors with the name of their parent device.
Enumerating the XML result, use the rename API call to rename them to 'Ping Cisco 1800', 'Ping Alarm', 'Ping CCTV', ....
/api/rename.htm?id=2186&value=Ping%20Cisco%201800
/api/rename.htm?id=2188&value=Ping%20Alarm
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