OpenGL render multiple objects using single VBO and updata object's matrices using another VBO

So, I need the way to render multiple objects(not instances) using one draw call. Actually I know how to do this, just to place data into single vbo/ibo and render, using glDrawElements.

The question is: what is efficient way to update uniform data without setting it up for every single object, using glUniform...?

How can I setup one buffer containing all uniform data of dozens of objects, include MVP matrices, bind it and perform render using single draw call? I tried to use UBOs, but it's not what I need at all.

For rendering instances we just place uniform data, including matrices, at another VBO and set up attribute divisor using glVertexAttribDivisor, but it only works for instances.

Is there a way to do that I want in OpenGL? If not, what can I do to overcome overheads of setting uniform data for dozens of objects?

For example like this:

{
    // setting up VBO
    glGenBuffers(1, &vbo);
    glBindBuffer(vbo);
    glBufferData(..., data_size);

    // setup buffer
    for(int i = 0; i < objects_num; i++)
        glBufferSubData(...offset, size, &(objects[i]));

    // the same for IBO
    .........
    // when setup some buffer, that will store all uniforms, for every object
    .........
    glDrawElements(...);
}

Thanks in advance for helping.