library(sf)

## Linking to GEOS 3.6.2, GDAL 2.2.3, PROJ 4.9.3

library(shadow)

## Loading required package: sp

library(mapview)

# Create line
pnt1 = st_point(c(663334.5462, 3517554.6530))
pnt2 = st_point(c(694000.4281, 3505649.8803))
line = c(pnt1, pnt2)
line = st_cast(line, "LINESTRING")
line = st_sfc(line)
line = st_set_crs(line, 32636)

mapview(line)

# Find azimuth
azimuth = classifyAz(as(line, "Spatial"))

# Draw other lines
n = 10        # How many lines to draw
d = 1000      # Distance between lines, in meters
result = list()
for(i in 1:n) {
  result[[i]] = shiftAz(as(line, "Spatial"), az = azimuth, dist = d * i)
}
result = lapply(result, st_as_sf)
result = do.call(rbind, result)

mapview(line, color = "red") + mapview(result)

## Warning in cbind(`Feature ID` = fid, mat): number of rows of result is not
## a multiple of vector length (arg 1)