It kinda depends on how harshly the players feel about others moving their characters.

a simple "they traveled through the murky wood together, neither saying much of anything due to the eerie stillness surrounding them." will cover it fairly well. Or you could do the same in several sentences.

If the players know each other well and understand the characters, then "remote control" on some level is also possible, though it might be wise to verify any points you have doubts about the correctness of in actions/words.