inability to import an old keystore type electrum.dat file into Sparrow wallet.
Electrum wallet.dat files are different from qt wallet.dat files and you cannot use the Electrum wallet.dat file to import into another wallet (correct me if I am wrong).
Looking through previous releases of Electrum (1.8 - 1.9.8 ) which date from around the time (2013) i created the wallet, has shown the seed type in the wallet files to be of an 'old' type, shown as a 32 character alphanumeric string,and the 'seed version' to be 4 in all releases.
However, the wallet i have has a wildly different type of seed in the keystore section of the wallet file - with a varied set of strings joined by plus signs, with an equals sign at the end of it, in a much longer overall string.
The 'seed version' number is also different, being 18.
I'm interested if anyone here can advise as to why my seed and version are so different.
So you have two different seed phrases that entirely belong to different wallets but did you try to import the wallet using the seed alone?
Just forgot the Sparrow wallet, try importing the wallet in the Electrum itself.