Attorneys recommend that you can say “No” as you are now using category C(26) for H4 EAD.
I have seen that it does not really matter even if you say “yes” and provide your old L2 EAD details.
The safer option would probably be to provide the L2 EAD details.
So, answer “New application or renewal” question as “New Application”.
Answer “have you filed form I-765 before” question as “yes” and then provide L2 EAD details in additional information section.
I have another general question - my current H-1B petition/visa is about to expire in Oct 2020, and if I file for EAD it would take somewhere between 3-7 months and by this time I would have submitted H-1B and H-4 extension. Not sure what is suitable option since I would like to ensure process on my end to get the EAD card is done before any changes happen to the H-4 EAD. Any suggestions?