I know of a lot of kids/youth that have played both and the ones who ended up choosing soccer develop a lot of good traits, particularly around toughness which helped them stand out as a soccer player.Depends what position... if you're asking a winger (in football) to make a Rugby League tackle no they probably wouldn't be able to because their game isn't built on strength but if you're asking a Centre Back or a Centre Defensive Midfielder or even a Striker I think they probably could.
In reverse I have heard of a few players over the years who have played soccer until their late youth and then made a successful switching rugby league, Colin Best former Sharks winger is one that comes to mind.