Different environment per Behat context (Symfony 4.x)

I want to create a lot of Behat features with simulating different configurations (from yaml,xml,php files).

Official extension for support Symfony 4 - Symfony2Extension have support for configuring a different environment like:

default:
    # ...
    extensions:
        Behat\Symfony2Extension:
            kernel:
               class: App\Kernel
               bootstrap: config/bootstrap.php
               env: custom_env

But, this extension is loaded before any suites or context. I should initial Kernel for each separate context with different config files via env.

Like:

default:
    suites:
        default:
            contexts:
                params:
                    env: custom_env
                - FeatureContext:

or

default:
    suites:
        default:
            contexts:
                - FeatureContext:
                    env: custom_env

And I'll load Kernel manually inside Context.

Any idea here?