Why are Nintendo DS ports lagging? (Inazuma Eleven 3)

The entire Inazuma Eleven 3 titles (Bomb Blast, Lighting Bolt and Team Ogre Attacks) still lags a lot in Citra while their sequels(Go Light/Shadow; Chrono Stones and Galaxy), that are way more graphic heavy with a lot of 3D stuff, run almost flawless. Hell, even Ultra Sun, Zelda and other 3D titles run smoothly, but these 2D games with some 3D here and there barely pass the 20 fps mark.

They were ported and localized in 3DS while their Japan versions are all in DS and run in 60 fps in Desmume and Drastic on weak Computers/Mobiles, yet in Citra they are disappointingly weak.

I wish I knew how to fix it

because I have the same problem