It might equipped with GN Drive[T], both Japanese Wiki and Pixiv Dictionary sugegst that it's at least consider (動力にはGNドライヴ［Τ］の搭載を検討している。 and 動力については擬似太陽炉の搭載が検討されている。). The Japanese Wiki outright list it as power source, while Pixiv play safe and doesn't list anything. --My girlfriend is a loli. 07:11, June 28, 2019 (UTC)
I thought Exia R4's left arm is because Graham is left-handed so in order to make Exia Graham Gundam more prominent for him. But after its Metal Built announced, its function is more than I know. "Kaina", something like the part from 6th Generation Gundam with new optimized GN Condenser will activate Partial Trans-am during slashing (not sure I read it correctly, I just found it recently). It does not have armour showing but the left arm frame alone is very durable. -- Rowanchang (talk) 15:15, February 22, 2020 (UTC)