Really? I wouldn't think the sun is nearly massive enough to do what would be required here. Stars visible near the edge of the Sun appear in slightly different spots from their actual locations. If there was a distant planet directly behind the Sun whose light were focused back to an image on our side of the Sun, you'd have to get really far back from the Sun to resolve the image, no? And furthermore, it's exceedingly difficult to orient such an apparatus to look in the desired direction; you are beholden to the orbital mechanics of your viewing satellite as it plods along.
Whereas, multi-site telescopes spread across the Earth have already been demonstrated as a feasible technology (recall the black hole images). It is well within our ability to set up a constellation of satellites, perhaps spanning a few of the Earth-Sun Lagrange points.