Mistral Large 3 2512 and InternVL3 78B are available through the OpenRouter API, so switching between them takes a model slug change rather than a new integration.
Mistral Large 3 2512, from Mistral AI, has a 262,144-token context window and is priced at $0.50/M tokens input, $1.50/M tokens output on OpenRouter.
InternVL3 78B, from opengvlab, is priced by the provider serving it on OpenRouter.