Sasuke body consist of Jugo dna,Hashirama dna,Kabuto dna.These dna Sasuke collected have varying sage mode origin.Jugo sage mode allow him to automatically nature energy without switching it off.Hashirama develop his own sage mode during his era.Kabutomaru get his sage mode from a combination of Jugo dna and Orichimaru dna.
Hashirama:
Hashirama give Sasuke his remaining Sage chakra
Kabuto
Jugo
Sasuke body adapt to jugo chakra since he have jugo dna and experience sage mode from curse mark
Sasuke possessing these sage mode dna/chakra variety,allow him to have resistance to absorbing sage chakra using prethra path.For example,If Naruto to use a sage mode resengan,Sasuke should be able to absorb the technique without turning into a toad because his body already familar with nature energy and have dna (from kabuto,hashirama and jugo) which act as a natural filter for his body.
Hashirama:
Hashirama give Sasuke his remaining Sage chakra
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Kabuto
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Jugo
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Sasuke possessing these sage mode dna/chakra variety,allow him to have resistance to absorbing sage chakra using prethra path.For example,If Naruto to use a sage mode resengan,Sasuke should be able to absorb the technique without turning into a toad because his body already familar with nature energy and have dna (from kabuto,hashirama and jugo) which act as a natural filter for his body.