Kronus is considerably more difficult than Teratomo, but still manageable. The lava phases can be tricky. Try to leave the health plants for when the lava phase begins or ends. You'll definitely want the health upgrade for this fight so that the plants provide more recovery when you use them.
The robots in between phases should be fairly easy since you'll have dealt with them during the investigation. If they prove difficult, you can use Kronus as a shield by keeping the tower between you and the robots until the health plants recharge.
Once the gas rings appear, use the highest ones to float. Just repeatedly tap
to hover inside the ring so you can aim at the targets on Kronus' facade. Once you've destroyed all the targets facing you, carefully turn and fly to the next gas ring. This is far easier than trying to strafe midair, as you are unlikely to find the next ring without facing it directly.