SEVIS indicates that my OPT has been approved. USCIS still shows "Case Was Received"

Usually USCIS updates are late to be posted and sometimes they are not

Am I able to petition/sponsor both my mother and husband?

Conflagrations on your marriage. You may file for both mother and spouse and there is no impact on either except that you will need sufficient...

How to process L2 EAD extension while our visa is still valid?

check PP validity date. Visa dat is not controlling the I-94 date is. File concurrent with spouse.

What year tax should I submit if I received a initial evidence, requesting for the most recent tax year?

2017 is the most recent tax year possible

As my colleagues indicate better to wait until you have renewed before seeking waiver.

Applied Change of status and my SEVIS got ended?

Based on the information provided there is no reason not to continue with adjustment in the US. For a full review see an immigration attorney

Can i apply for motion to reopen while i am waiting for approval from i-130 ?

The I-130 should be approved and more. Contact an immigration attorney.

reactivation - no. Refile - possible. Speak with the employer's immigration attorney.

I am about to apply for US naturalization and they changed my previous address.

provide the street address as it is now

Will I accumulate unlawful presence?

Have you spouse file a visa petition and you file concurrently for adjustment as soon as possible.