According to rumours Firmino have got an offer from Juventus which is worth 19.5 million pounds. However Liverpool are indecisive about selling him or not. If they do so they might need to fill his place with a rotation player. There is Diogo Jota also who can play as a centre-forward but he is mainly a winger. He would be the only alternative for Nunez if they don't sign anyone. Liverpool have seemed positive about selling Firmino lately actually so they might agree upon a deal with Juventus.
If the rumors are true, it will be a good move for Firmino. I would love to see him take up a new challenge is career as it already feels like his time at Liverpool is coming to an end, he is no longer as valued and important in the team as he was few years back and a move now will be good for him, he needs a new atmosphere and a new experience at the level in his career and I believe he will happy to take on a new challenge elsewhere.