Sell and re-buy (whether that's the same company stock or something else) is preferable.

There's no tax benefit if the share price is flat or up and you lose the capital loss if it's down. The only real benefit is avoiding trade commission to sell and buy again. Your brokerage may cover transfer costs but that isn't certain so you could end up paying more. Trade commission should be < $20 to do the moves even if you use an expensive big-bank brokerage so your potential benefit is tiny.

I haven't tried in a long time but with computershare the process took weeks. Maybe shareworks or whatever your company uses is better. During the transfer your stock is inaccessible.

Given that you can sell on Monday and buy on Friday there seems like very little reason to do an in-kind transfer even if you plan to hold your employer's shares until you die.