Many terminal (drain to ocean) flowpaths are digitized the wrong way.
When extracting starting and ending nodes for terminal network flowpaths (almost all I have seen drain to the coast) the LINESTRING is reversed.
This issue seems to originate in the reference fabric.
One example is COMID 2676184.
pacman::p_load(sf, dplyr, mapview, nhdplusTools) ex = read_sf("/Volumes/Transcend/ngen/CONUS-hydrofabric/reference/reference_01.gpkg", 'reference_flowline') %>% filter(COMID == 2676184) mapview(ex) + get_node(ex, 'end')
Created on 2022-09-23 by the reprex package (v2.0.1)
Others I quickly see include: 2676092, 2676162, 2676174