It is possible to file a change of employer petition for the H-1B. If you use premium processing, you can get a decision in 15 days. The issue is whether you will make yourself ineligible for the L-2 EAD if you change status. If you do decide to change, you will be able to change back to L-2 as long as your spouse maintains their L-1. You should consult with an attorney who can review your documents and the law to make a specific determination of the risks associated with this strategy before you decide to file.
This answer is intended to provide general information and should not to be construed as legal advice pertaining to a particular situation or relied upon as such. You should have your specific situation reviewed by an attorney.