This puzzle has two versions with different solutions. This version is Fers non-consecutive (FNC) diagonally. 17(3) cage at R3C2 has one number repeated.
Prelims
a) R78C1 = {59/68}
b) R56C2 = {59/68}
c) 28(4) cage at R1C1 = {4789/5689}, no 1,2,3
d) 13(4) cage at R3C1 = {1237/1246/1345}, no 8,9
e) 14(4) cage at R8C4 = {1238/1247/1256/1346/2345}, no 9
f) 28(4) cage at R8C8 = {4789/5689}, no 1,2,3
g) 17(3) cage at R3C2 with repeated number = {449/557/665/773/881}, no 2
Steps resulting from Prelims
1a. 28(4) cage at R1C1 = {4789/5689}, 8,9 locked for N1
1b. 13(4) cage at R3C1 = {1237/1246/1345}, 1 locked for C1
1c. 28(4) cage at R8C8 = {4789/5689}, 8,9 locked for N9
2a. R1C1 + R2C2 or R2C1 + R1C2 cannot be {89} (FNC) -> either R1C12 or R2C12 = {89}
2b. R8C8 + R9C9 or R8C9 + R9C8 cannot be {89} (FNC) -> either R8C89 or R9C89 = {89}
2c. Killer pair 8,9 in R1C1 or R2C2 + R8C8 or R9C9, locked for D\
2d. Killer pair 8,9 in R12C1 and R78C1, locked for C1
2e. Killer pair 8,9 in R12C2 and R56C2, locked for C2
3. 45 rule on C1 2 outies R12C2 = 1 innie R9C1 + 10
3a. Max R12C2 (because of step 2a) = 16 -> max R9C1 = 6
4. 17(3) cage at R3C2 with repeated number must have repeated number in R3C2 = {449/557/665/773}, no 1,8 -> R3C2 = {4567}
4a. 7 in C1 only in R123456C1 -> 17(3) cage cannot be {773}, no 7 in R3C2, no 3 in R45C3
4b. 17(3) cage cannot be {665} (which clashes with R56C2) -> 17(3) cage = {449/557}, no 6
4c. R56C2 = {68} (cannot be {59} which clashes with 17(3) cage), locked for C2 and N4
4d. 8 in N1 only in R12C1, locked for C1, clean-up: no 6 in R78C1
4e. R78C1 = {59}, locked for C1 and N7
4f. Naked pair {68} in R56C2 -> no 7 in R456C13 (FNC)
4g. 17(3) cage = {449} (only remaining combination) -> R3C2 = 4, R45C3 = {49}, locked for C3 and N4
4h. R3C2 = 4 -> no 3,5 in R2C3, no 3 in R4C1 (FNC)
4i. Naked triple {123} in R456C1, locked for C1 and N4 -> R6C3 = 5, R4C2 = 7, no 6 in R3C13, no 6 in R5C2, no 4,6 in R57C4 (FNC)
4j. R3C1 = 7, naked pair {68} in R12C1, locked for C1 and N1 -> R9C1 = 4, placed for D/, no 3 in R8C2 (FNC)
4k. R56C2 = [86] -> no 9 in R4C3, no 5 in R7C1, no 7 in R7C3 (FNC)
4l. R78C1 = [95]
4m. 45 rule on N9 2 remaining innies R9C23 = 9 = [18/27/36]
4n. Naked triple {123} in R123C3, locked for C3
4o. 3 in C3 only in R13C3 -> no 2,4 in R2C4 (FNC)
4p. R7C3 = {68} -> no 7 in R68C4 (FNC)
4q. R45C3 = [49] -> no 3,5 in R35C4, no 8 in R6C4 (FNC)
5. 14(4) cage at R8C4 = {1346} (cannot be {1238/1247} which clash with R8C2), locked for R8
5a. 28(4) cage at R8C8 = {5689} (only remaining combination), no 7
5a. Naked pair {89} in R8C89, locked for R8 and N9
5b. Naked pair {56} in R9C89, locked for R9 and N9
5c. R8C2 = 2, placed for D/, R8C3 = 7, R9C3 = 8 -> R9C2 = 1 (step 4m), R7C2 = 3, R7C3 = 6, placed for D/, no 2 in R6C1, no 8 in R7C4 (FNC)
5d. 3 in N9 only in R89C7, locked for C7
5e. Naked quad {5689} in R1C1 + R2C2 + R8C8 + R9C9, locked for D\
5f. 8 in C4 only in R123C4, locked for N2
6! 4 on D\ only in R6C6 + R7C7 -> no 4 in R6C7 + R7C6 (CPE), no 3 in R6C6 (FNC)
6a! 3 on D\ only in R3C3 + R4C4 + R5C5 -> no 2 in R4C4 (FNC)
6b. R4C4 = {13} -> no 2 in R3C3 (FNC)
6c. Naked pair {13} in R3C3 + R4C4, locked for D\ -> R5C5 = 7, placed for both diagonals, no 8 in R4C6 (FNC)
6d. Naked pair {13} in R3C3 + R4C4 -> no 1 in R3C4 (CPE)
6e. R4C4 = {13} -> no 2 in R3C5 (FNC)
6f. Naked pair {24} in R6C6 + R7C7 -> no 2 in R6C7 + R7C6 (CPE)
6g. 7 in N8 only in R79C46 -> no 6 in R8C5 (FNC)
6h. 6 in N8 only in R8C46 -> no 5 in R7C5 (FNC)
6i. 8 on D/ only in R1C9 + R2C8 + R3C7, locked for N3
6j. 8 on D/ only in R1C9 + R2C8 + R3C7 -> no 9 in R2C8 (FNC)
6k. 5 in N8 only in R7C46 -> no 4 in R68C5 (FNC)
6l. R8C5 = {13} -> no 2 in R7C4 + R9C46 (FNC)
6m. 2 in R9 only in R9C57 -> no 1,3 in R8C4 (FNC)
6n. 2 in N8 only in R79C5, locked for C5
6o. 2 in N8 only in R79C5 -> no 1,3 in R8C4 (FNC)
6p. Naked pair {46} in R8C46, locked for R8 and N8
6q. 4 in N8 only in R8C46 -> no 3 in R9C5 (FNC)
6r. R8C7 = {13} -> no 2 in R7C8 (FNC)
7. R7C6 = 8 (hidden single in C6) -> no 9 in R6C5, no 7,9 in R6C7 (FNC)
7a. R7C4 = 5 (hidden single in R7)
7b. 7 in R7 only in R7C89, locked for N9
7c. 4 in N5 only in R56C6, locked for C6 -> R8C46 [46]
7d. R4C5 = 6 (hidden single in N5) -> no 5 in R35C6 (FNC)
7e. R4C6 = 5 (hidden single in N5), placed for D/
7f. R6C5 = 8 (hidden single in N5), R6C7 = 1, R6C1 = 3, R6C4 = 9, placed for D/, R3C7 = 8, R8C57 = [13], R9C57 = [92], R7C5 = 2, R7C7 = 4, placed for D\, R6C6 = 2, R5C4 = 1, R4C4 = 3, placed for D\
8. 7 in C7 only in R12C7, locked for N3
8a. Naked pair {13} in R1C9 + R2C8, locked for N3
8b. R1C9 + R2C8 = {13} = 4 -> R1C8 + R2C9 = 13 = {49}, locked for N3
and the rest is naked singles, without using the diagonals or FNC.