Enable the WP API OAuth Server consumer UI to create key pairs without using WP CLI.

enable-wp-oauth-ui.php

<?php
/*
Plugin Name: Enable OAuth UI
Plugin URI: https://gist.github.com/rheinardkorf/dab0f0f46b814e1a7d1d
Description: Allows you to create consumer key pairs without WP CLI and the ability to name them for each APP. Must have WP API Oauth Server plugin active.
Version: 0.1
Author: Rheinard Korf
Author URI: https://gist.github.com/rheinardkorf/
License: GPL2
License URI: http://www.gnu.org/licenses/gpl-2.0.html
*/

function rk20151105_enable_oauth_ui( $args, $post_type ) {

    if( $post_type === 'json_consumer' ) {
        $args['show_ui'] = true;
        $args['supports'] = array('title');
        $args['labels'] = array(
            'name' => __( 'API Consumer' ),
            'singular_name' => __( 'API Consumers' ),
        );
    }

    return $args;
}
add_filter('register_post_type_args', 'rk20151105_enable_oauth_ui', 1, 2 );

function rk20151105_add_consumer_meta( $post, $args ) {

    $key = get_post_meta( $post->ID, 'key', true );
    $secret = get_post_meta( $post->ID, 'secret', true );
    $type = get_post_meta( $post->ID, 'type', true );

    if( empty( $key ) ) {
        $consumer_meta = array(
            'key'    => wp_generate_password( WP_JSON_Authentication_OAuth1::CONSUMER_KEY_LENGTH, false ),
            'secret' => wp_generate_password( WP_JSON_Authentication_OAuth1::CONSUMER_SECRET_LENGTH, false ),
        );
        $consumer_params = array( 'meta' => $consumer_meta, 'ID' => $post->ID );

        rk20151105_update_consumer_meta( $consumer_params );

        $key = get_post_meta( $post->ID, 'key', true );
        $secret = get_post_meta( $post->ID, 'secret', true );
        $type = get_post_meta( $post->ID, 'type', true );
    }

    echo '<div><strong>Object ID:</strong> ' . $post->ID . '</div>';
    echo '<div><strong>Key:</strong> ' . $key . '</div>';
    echo '<div><strong>Type:</strong> ' . $type . '</div>';
    echo '<div><strong>Secret:</strong><span class="secret-to-hide" style="display:none;"> ' . $secret . '</span></div>';
    echo '<div><span class="secret-toggle button button-primary">Show/Hide</span></div>';
    echo '<script>jQuery(".secret-toggle").on("click", function() { jQuery(".secret-to-hide").toggle(); } )</script>';

}

function rk20151105_add_meta_boxes() {
    add_meta_box(
        'meta-box-one',
        __( 'Consumer Meta' ),
        'rk20151105_add_consumer_meta',
        'json_consumer',
        'normal',
        'high',
        array()
    );
}
add_action( 'add_meta_boxes', 'rk20151105_add_meta_boxes' );

function rk20151105_update_consumer_meta( $params ) {

    $default = array(
        'name' => '',
        'description' => '',
        'meta' => array(),
    );
    $params = wp_parse_args( $params, $default );

    $ID = $params['ID'];
    unset( $params['ID'] );
    $meta = $params['meta'];
    $meta['type'] = 'oauth1';
    $meta = apply_filters( 'json_consumer_meta', $meta, $ID, $params );

    foreach ( $meta as $key => $value ) {
        update_post_meta( $ID, $key, $value );
    }
}

function rk20151105_admin_notice() {
    if( ! class_exists( 'WP_JSON_Authentication_OAuth1' ) ) {
        ?>
        <div class="updated">
            <p>Please install the WP API OAuth Server Plugin ( <a href="https://github.com/WP-API/OAuth1">https://github.com/WP-API/OAuth1</a> ) for Enable OAuth UI to work.</p>
        </div>
        <?php
    }
}
add_action( 'admin_notices', 'rk20151105_admin_notice' );

@harzer-knaller, I apologize for such an incredibly late reply.

This was proof of concept and will not work without WP-API/OAuth1 plugin installed.