Samurai Jack- Strategy help

[Xionzenn]

For anyone that has Samurai Jack (PS4), I'm 4 stages away from completing the game on Masters of Masters, it's extremely difficult not being max skilled so I want to replay some levels on beginner difficulty & boost my skills up to make it less of a hassle for me. My questions are:

 

1- If I replay some levels without finishing my remaining levels on beginner level to boost my skill, will that affect my Masters of Masters trophy? 

 

2- I ran easily out of haggis too, can I go back and get a few and use that in my next playthrough?

 

Considering stopping here till I get some advice, since I got two lucky breakthroughs in the last two bosses because there was a glitch I exploited by chance.  The next level is going to be no joke, Scaramouche is going to need me fully maxed to beat him.