This is my fear too. Liverpool at their peak relied on their wingers for much of their goal threat. When you put in a striker who wants to be doing a lot of the same things as your wingers you nullify their effectiveness. We can already see to some extent that issue with Wout and how he is more effective playing deeper a lot of the time. I know Wout is not an elite striker but I fear that unless we got someone like Kane who is also a very very good playmaker and used to working with an elite winger who scores goals it could be detrimental for Rashford.
I prefer Kane myself, too, but I don't agree with Liverpool example. Remember that Klopp didn't buy Salah himself, it was pushed on him. At Dortmund, Klopp forward line is different. Now Mane left, and Klopp has to try to reinvent Liverpool forward line. He can't always get the same profile of player at the same quality to replace Mane or Lewandolski at Dortmund.
Wout should not be used in anything type of discussion as a base for our search of future CF because as a CF WW is out of depth at our level. He's being shoehorned so he can at least use his best attribute. Rashford would score regardless whether WW is on the pitch or not. In the summer, we were looking to purchase a forward with different profile like Arnautovic, Cunha, Morata... in meanwhile Weghorst was on loan to Turkey for first half of the season. WW only came here because Ronaldo left, where the option on the market was too limited for us to be picky.
I don't know where some people have this idea that Osimhen playing CF the same way as Rashford. Osimhen is likened to Drogba because he's handful, assertive. He challenges defenders face to face, body to body. He occupies, screening the defenders with his back to goal, fighting for percentage ball. He can run in behind, run channel because he has pace, and it's part of CF responsibility, but it's not his main focus like Rashford's specialty in off ball movement. Run the channel, run behind is not a hinderance for another player, if the run is well coordinated, where one runner is the decoy for another runner to find favored space. Mourinho always wanted Eto'o at Chelsea to pair with Drogba. Later on he got Eto'o at in Inter and played Eto'o wide, but without a Drogba type of CF. At the same time Chelse's bought Anelka, and Ancelotti used Anelka in similar wide forward tactical profile where Chelsea had the most free goal scoring PL season with quite a few tennis scoreline.
Kane is more tactical flexible because he can play like a play making midfielder, which is useful to switch for more control in midfield at willl