Need help changing employers with H1 Extn in progress

My H1 B expired on 30 september and my visa extn is in progress. they applied extn on 27th April. Now the project I am working is winding up their work and we were asked to leave. Now my company do not have any projects outside.

Is it possible to transfer H1 when H1B extn is in progress?

If I get RFE from my previous extn and with me no longer working with that client how that will work since the previous employer will not be willing to help me on this as I no longer work with him.

I assume your I-94 has expired (30 Sep). So you cannot go for H-1 transfer independent of what happens to your pending extension petition.

You can apply for H-1 transfer with consular processing, then leave US and return on stamped visa and petition. However, if you want to change jobs w/o leaving US that is dependent on existing extension getting approved (as it would issue a new I-94).