[lch]

As Sombre said, it isn't too much. Here's the list of national spells by nation:

0 - [160, 811]
1 - []
2 - [157, 158]
3 - [799, 800, 811]
4 - [193, 194, 803]
5 - [187, 188, 189, 190, 191, 192, 193, 194, 775, 808, 810]
6 - []
7 - [175, 176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 806]
8 - [767, 769, 773]
9 - [165, 761]
10 - [161, 162, 163, 164, 768]
11 - [145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 811]
12 - [222, 224, 225]
13 - [141, 142, 143, 797]
14 - [794, 795, 801, 802]
15 - []
16 - [172]
17 - [173, 174]
18 - [195, 197, 198, 199, 201, 203, 205, 206, 774, 793, 809]
19 - [208, 210, 212, 213, 214, 216, 217, 771, 772, 850, 857]
20 - [845, 846, 847, 848, 849]
21 - [781]
22 - []
23 - []
24 - []
25 - []
26 - []
27 - [160, 811]
28 - [102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113]
29 - [166, 167, 168, 169]
30 - [141, 142, 143, 794, 795, 796]
31 - [157, 770, 832, 833, 834]
32 - [166, 167, 168, 169, 274]
33 - [175, 176, 177, 178, 179, 180, 181, 182, 184, 185, 186, 806]
34 - [187, 189, 190, 192, 775, 807, 808, 810]
35 - []
36 - [222, 226, 227, 228, 229, 234]
37 - [767, 769, 773]
38 - [165, 761]
39 - [161, 162, 163, 164, 768]
40 - [145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 811]
41 - [172]
42 - [173, 174]
43 - [195, 196, 197, 198, 199, 200, 201, 202, 203, 204, 205, 206, 774, 782, 783, 784, 785, 786, 787, 788, 789, 790, 791, 792, 793, 809]
44 - [207, 209, 210, 211, 212, 213, 214, 215, 216, 217, 218, 219, 220, 221, 857]
45 - [837, 838, 839, 840, 841, 842, 843, 844, 846, 847, 848, 849]
46 - [781]
47 - []
48 - []
49 - [160, 811]
50 - [102, 103, 104, 105, 106, 107, 108, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131]
51 - [794, 795, 796, 798]
52 - [157, 158, 159, 770, 832, 833]
53 - [166, 167, 168, 169, 170, 171, 274]
54 - [175, 176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 806]
55 - [187, 189, 190, 192, 193, 194, 775, 808]
56 - [207, 208, 209, 210, 211, 212, 213, 214, 215, 216, 217, 218, 219, 220, 221, 851, 852, 853, 854, 855, 856, 857, 858, 859, 860, 861, 862, 863]
57 - [222, 230, 231, 232, 233, 234, 235, 236, 237, 238]
58 - [767, 773, 830, 831]
59 - [165, 761]
60 - [132, 133, 134, 135, 136, 137, 138, 139, 140, 162, 163, 164, 768]
61 - [145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156]
62 - [172]
63 - [173, 174]
64 - [195, 197, 198, 199, 201, 203, 205, 206, 782, 783, 784, 785, 786, 787, 788, 789, 790, 791, 792, 793, 809]
65 - [836, 839, 840, 841, 842, 843, 844, 846, 847, 848, 849]
66 - [765, 781]
67 - [239, 240]
68 - [782, 783, 784, 785, 786, 787, 788, 789, 790, 791, 792]
69 - [141, 142, 143, 797]
70 - [803, 804, 805]
71 - [813, 814, 815, 816, 817, 818, 819, 820, 821, 822, 823, 824, 825, 826, 827]

Fishing out spells that are unique to an era and not used across multiple ones, this leaves the following to overwrite:

• EA: [102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 159, 166, 167, 168, 169, 170, 171, 196, 200, 202, 204, 207, 209, 211, 215, 218, 219, 220, 221, 226, 227, 228, 229, 230, 231, 232, 233, 234, 235, 236, 237, 238, 239, 240, 765, 770, 274, 796, 798, 804, 805, 807, 813, 814, 815, 816, 817, 818, 819, 820, 821, 822, 823, 824, 825, 826, 827, 830, 831, 832, 833, 834, 836, 837, 838, 839, 840, 841, 842, 843, 844, 851, 852, 853, 854, 855, 856, 858, 859, 860, 861, 862, 863]
• MA: [114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 158, 159, 170, 171, 183, 188, 191, 193, 194, 208, 224, 225, 230, 231, 232, 233, 235, 236, 237, 238, 239, 240, 765, 771, 772, 798, 799, 800, 801, 802, 803, 804, 805, 813, 814, 815, 816, 817, 818, 819, 820, 821, 822, 823, 824, 825, 826, 827, 830, 831, 836, 845, 850, 851, 852, 853, 854, 855, 856, 858, 859, 860, 861, 862, 863]
• LA: [769, 771, 772, 774, 141, 142, 143, 797, 799, 800, 161, 802, 807, 810, 188, 191, 834, 196, 837, 838, 801, 200, 202, 204, 845, 850, 224, 225, 226, 227, 228, 229, 109]