Writer AI and less known general purpose and domain specific LLMs

Hi, I’m jumping across domains and industries for my AI work, and having the ability to chat and work through different LLMs, namely the Palmytra LLMs series by Writer AI, MiniMax, Exaone, Phi4 by Microsoft, Amazon Models, etc would be hugely helpful. Given that many are already hosted or have openrouter connections should make it an easy fix?