Okay funny thing right now... I looked some more into the GBAExploder with the hint of a Thread in my mind that I need to get the savegame which is from my smartphone on some way into the memory of the ez-flash 3in1.
so I did the following:
I removed every save game files (.sav / .gba.sav) from...
I use Flash 128k. Savegame was original created with Visual Boy Advance and then i loaded it on my Android Smartphone with GameBoid without any problems. I tried the conversion with "NDS Save Converter v2.6" which can convert NDS and GBA games but it didnt help at all (i tried the RAW and AKAIO)...
Okay after like 5 hours of googling and always getting to this forum i think i get some help here (even though the answers didnt really helped in my case).
After playing for some time ony my android phone pokemon leaf green i decided to get my NDS back in action because its way cooler to play...