There is an option in the animations to ignore the skeletal meshes rotation etc (set by default) - you can change that in each of the animations to “Local” or “Mesh” but that may introduce problems of it’s own.
I’d go with the rotate the skeleton base in each anim (click on base bone, add key, rotate bone 90* and save).
I started writing a plugin to do it - do you think it would be a handy plugin worth about $20? (select as many anims you want, right click → select +90* menu item → done)