How will an EB-5 application impact my current L-1 visa?

Not at all as the L-1A and L-2 are dual intent statuses. Make sure status is maintained until the green cards are approved.

The L-1 is a dual intent visa so it will not have any impact.

Starting an EB-5 case, i.e., your wife filing an I-526 petition, will not affect your L-1 visa/status or the L-2 visa/status of your wife and children. The L category is a "dual intent" visa category and, therefore, applying for an immigrant classification such as EB-5 does not affect your non-immigrant L classification.

If you have a knowledgeable immigration lawyer, your wife applying for an EB-5 should not affect you at all.

No, L-1 is dual intent.

Can be done, and if setup correctly, may be a way to lawfully remain in the U.S. as the I-526 remains pending (depends on your goals/intentions though). But best to structure carefully. The fact that you have two separate petitions helps (and that you would be a beneficiary).

Applying for an EB-5 Green Card should not negatively affect L-1/L-2 statuses as they are "dual intent" statuses.

There should be no effect. Your wife can apply for EB-5 even though you are on L-1 visa.

No, it will not impact your L1 visa.