  Under the hypothesis that self-reproducing probes have formed a
galactic-scale communication network by direct Gravitationally-Lensed (GL)
links between neighboring systems, we identify Wolf 359, the third nearest
stellar system, as an excellent target for a search for alien interstellar
communication emitted from our Solar System. Indeed, the Earth is a transiting
planet as seen from Wolf 359, meaning that our planet could pass in an alien
communication beam once per orbit. We present a first attempt to detect optical
messages emitted from the Solar System to this star, based on observations
gathered by the TRAPPIST-South and SPECULOOS-South robotic telescopes. While
sensitive enough to detect constant emission with emitting power as small as
1W, this search led to a null result. We note that the GL-based interstellar
communication method does not necessarily require to emit from the so-called
"Solar Gravitational Line" (SGL), starting at ~550 au from the Sun, and that
the probe(s) could be located closer to the Sun and off-center relative to the
SGL, at the cost of a smaller but still significant gain compared to a
non-GL-boosted communication strategy. Basing on this consideration, we
searched in our data for a moving object whose motion would be consistent with
the one of the hypothesized alien transmitter, assuming it to use a solar sail
to maintain its distance to the Sun. We could not reliably identify any such
object up to magnitude ~23.5, which corresponds to an explored zone extending
as far as Uranus' orbit (20 au).
