Try Sonic Visualizer you can export the tempo map as a txt or csv File > Export Annotation Layer
https://www.sonicvisualiser.org/
I just made a script to get the chords from audio then import that into Reaper's regions from Sonic Visualiser using Chordino,
so should be able to change it to tempo markers.
txt
Code:
0.000000000 123.047 123.05 bpm
11.888616780 120.185 120.19 bpm
16.346848073 123.047 123.05 bpm
28.235464853 120.185 120.19 bpm
29.721541950 123.047 123.05 bpm
31.207619048 120.185 120.19 bpm
32.693696145 123.047 123.05 bpm
38.638004535 120.185 120.19 bpm
40.124081633 123.047 123.05 bpm
44.582312925 120.185 120.19 bpm
47.554467120 123.047 123.05 bpm
52.012698413 120.185 120.19 bpm
56.470929705 123.047 123.05 bpm
69.845623583 120.185 120.19 bpm
71.331700680 123.047 123.05 bpm
75.789931973 120.185 120.19 bpm
77.276009070 123.047 123.05 bpm
78.762086168 120.185 120.19 bpm
.....
.....
or csv
Code:
0.000000000,123.047,123.05 bpm
11.888616780,120.185,120.19 bpm
16.346848073,123.047,123.05 bpm
28.235464853,120.185,120.19 bpm
29.721541950,123.047,123.05 bpm
31.207619048,120.185,120.19 bpm
32.693696145,123.047,123.05 bpm
38.638004535,120.185,120.19 bpm
40.124081633,123.047,123.05 bpm
44.582312925,120.185,120.19 bpm
47.554467120,123.047,123.05 bpm
52.012698413,120.185,120.19 bpm
56.470929705,123.047,123.05 bpm
69.845623583,120.185,120.19 bpm
71.331700680,123.047,123.05 bpm
75.789931973,120.185,120.19 bpm
77.276009070,123.047,123.05 bpm
78.762086168,120.185,120.19 bpm
80.248163265,123.047,123.05 bpm
92.136780045,120.185,120.19 bpm
96.595011338,123.047,123.05 bpm
99.567165533,120.185,120.19 bpm
104.025396825,123.047,123.05 bpm
....
....