Lol you seem sadly misinformed. Apart from tejas mk2, none are LCA based designs. Tedbf has 2 engines and frontal stealth etc, with diff design too. Amca is a full on stealth fighter. And IN has already expressed interest for N-AMCA. The whole hullabaloo about naval jet is due to navy wanting a dual engine fighter, due to higher payload capacity (absent on n-lca, it was too underpowered).
I'm common citizen IT engineer, not defence journalist, hence i comment only on technology, not the procurement dealings, politics, etc of it. And i'm not misinformed on technical part.
Although i do watch many things like talk shows like "Security Scan"on RajyaSabhaTV & SansadTV channels, which show top journalists & retired generals, air chief marshals, admirals, etc, but I don't have time to monitor each & every discussion, persuading talks, disagreements b/w armed forces, governments, OEMs, etc.
Now, TEJAS which is a naming nomenclature, can be treated as just another word for SERIES. Currently LCA is nown as TEJAS but there was MCA preliminaly design also from beginning, which can be called MK2. Hence i mentioned that all acronyms used (TEDBF/ORCA/AMCA/MWF/MRCA/MRFA/blah-blah-blah) for a medium jet need to be same airframe to save cost for Navy & Air-Force.
Due to political scams we made massive delays with LCA, i hope same won't repeat for MCA/MWF/MRFA/MRCA/AMCA/blah-blah-blah, whatever people wan't to call it.