Should I change my forward?

I have 3 forward, 2st and 1 amc. They performed very well last season (together they score 110++goals in less than 50 games and 60+ assist). This season, they have lose a star,2four stars and 1five stars. Should I change them? I am worrying about whether the can score in cup, there are much more higher level team(less than 20 same lvl with me)

Cup is about quality, not level. If they did fine last season, then you should be loyal to them and trust they can get it done for you this season. If you don't feel confident with them be on the lookout for a forward on the transfer market and be patient for a good deal to come along