Orlando gets the lowered resistances, but the negative effects are so low at Lv20 that they're barely noticeable
You'd want to upgrade Thunder God passive. At the start, the effects can be very glass cannon. But as you upgrade, you increase your attack but you shave down the negative resistances. Basically, you increase "All attack resistances" with each upgrade until the negative effects are so low, it's barely noticeable or it's gone entirely.
Testing raising ability jp lvls. Negative effects apply to Orlandeau. Each upgrade increases 1% up except lvl 10, 15. Not sure if 5 did or if 20 will only raise atk as I was not looking at this until lvl 10 when I noticed it. Currently I'm at lvl 17.