Can USCIS cancel or revoke the Green card?

You are correct, CIS 'usually' doesn't cancel greencards after 5 years ... but, they can deny US citizenship (naturalization).

During this Corona situation, which process is better to opt (adjustment of status or counselor processing)?

Assuming that your spouse is a US citizen, do an AOS ... .but, don't plan on leaving the US for 9-12 months.

There will be some legal way of having a work authorization contested given the long delay of so many years to wait for answer?

I agree with Mr. Berman ... you should qualify for a work permit ... unless you did something to 'stop the clock'.

Can I day trade if my H1B has expired?

I always advise against day trading unless people have a greencard (or are a US citizen.)

When can I get permanent green card through counselor processing?

I am going to assume that your spouse is NOT a US citizen. I agree with my colleague, it is better to file NOW and not leave the US.

How can I find out what is the reason of my J 1 Au pair visa is terminated or ended?

You can try filing a FOIA with the DOS.

How long after submission of an I130 do i get informed whether anything is missing !

I agree with my colleague, you should hear something in 2-4 months.

Oh forgot to mention that submitted petition i130 was for an unmarried daughter over 21 for u.s.ctizen?

I agree with my colleague, generally 2-4 months.

Yes, Consular Visa Officers are qualified to grant this exception. Usually, it is best if an attorney includes a legal brief.

I absconded from probation and want to get my passport?

I predict that this will NOT work ... the NCIC database is 'national' and even has an overlay with INTERPOL. And, you are correct ... you need...