H4 EAD Filing while H4 extension/ transfer is in process


Please guide for below below mention situation :

I am working in company ‘A’ and planned to to join company ‘B’ within next 1 month. I got my H1B transfer approved for company ‘B’ and they have filed my spouse’s H4 (NOT EAD).
I am not sure who the attorney is for company ‘B’, However, they have shared the approved H1B petition and spouse’s receipt notice with me.

Q 1. Though, H4 is not approved yet, can I file H4 EAD for my spouse ?
Q 2. Since, H4 has been filed by some attorney, can I file H4 EAD at my own?
Q 3. Or Shall I wait until H4 is approved ?

Thanks in advance !