sq = function(pt, sz = 1) st_polygon(list(rbind(c(pt - sz), c(pt[1] + sz, pt[2] - sz), c(pt + sz), c(pt[1] - sz, pt[2] + sz), c(pt - sz))))
x = st_sf(box = 1:6, st_sfc(sq(c(4.2,4.2)), sq(c(0,0)), sq(c(1, -0.8)), sq(c(0.5, 1.7)), sq(c(3,3)), sq(c(-3, -3))))
plot(x)
st_overlaps(x)