Sorry, but you got it wrong. Delta is at D/E T2 and LH is at A T1 (it could also be B1-13 Schengen gate at T1)
If your incoming flight is on time there is a fair chance that you will make it in time to the A gate of your LH flight. As long as you accept that there is high risk that you miss the LH flight (if e.g. the DL flight gets into FRA late or the lines for security check are long) and you would have to pay for either a new ticket or expensive rebooking, you could try it.
You should take the SkyLine train from D/E at T2 to A/Z at T1 - after clearing immigration and exiting the transfer area. It will require you to go through security check at A/Z T1 and the lines are often long. I'm not sure you can remain in transit without having to pass security check when arriving D/E at T2 and going to A T1. Anyway, it is quite a long walk from D/E T2 to A T1.
Last edited by SK AAR; Jun 24, 2019 at 5:40 pm