Best way to do magnification

I am rendering to framebuffer of size 512x512 (texture attachment). And I want this to be rendered on another FBO of size 1k x 1k. I can do render to texture with full screen quad. But I am wondering is it possible to do this in single pass directly to final FBO? Can we write to multiple fragment locations from fragment shader or something similar functionality? I am using ES 3.0.

Look into glBlitFramebuffers, but I’m not sure this is faster than an actual pass with a simple shader.