As LT has given the Western Isles version of events I'll offer those of the Central Belt...
Cremations are by far the most common of arrangements here and most funerals take place in crematoria with services in the Hall being uncommon. It's been rare for me to see anyone other than undertakers carry the coffin into the crematorium at either JW or non JW funerals. Of the burials I have attended it has again been undertakers carrying the coffin but with male relatives lowering the cords into the grave, with no difference between JW and non JW burials. The sexism of funeral behaviour is not a JW thing.
The exception to all these was the funeral of a JW teenager who had cystic fibrosis. The service was in the KH with the closed coffin present and carried by six sisters - despite it being somewhat contrary to cultural norms it caused no fuss.