…のも無理 (は) ない => It's natural for... N3
Evaluate
に代わって => instead of; replacing; on behalf of ~ N3
のも無理もない => (to be) natural,(to be) understandable N3
Evaluate
代わりに => instead of; as a substitute for​; in exchange for; in return for N3
[代「か」]わり => Not A, but B, B in place of A, Instead of A, B; In exchange for A, B N3
Comparison, Exchange