All separators r not the same! I use thicker separator’s which I found on Amazon and they have not given out on me. A quick rinse under hot water keeps them in good condition. Others that I have tried get smooshed and turn black over time. I have not had that problem with these.
Povihome 10 Pack Toe Spacers Separators(1/2'' Thick), Bunion Corrector Gel Orthotics for Bunion, Overlapping Toes - L Size https://www.amazon.com/dp/B0734KRL5N/ref=cm_sw_r_cp_api_glt_i_2BTK0EXR8TPWRJHB0VY2
People at risk for bunions have feet with unusually wide spacing between the toes. In the pre-shoe era, this would have been adaptive as it would have allowed toes to spread and grip the ground. With shoes, any pressure against the side of the toe is going to result in a more acute angle, and the joint will deform, because the toe is not supported by an adjacent toe on the other side.
If you look at people without bunions, you will note that their toes are generally closely spaced and support each other, so that lateral pressure does not cause the big toe joint to angle inwards.
So what do we do? Wearing shoes with a wide forefoot is a good first step. You say that altra doesn't work for you, but have you tried topo? Topo shoes have similarly wide toe-boxes, but they also have a slight rise.
Next up, if you're wearing shoes at all, even if they're wide, you will still get occasional lateral pressure on the toe that will increase the angle and thereby increase the size of the bunion. The only way to slow this down is to wear spacers between your toes, under your socks.
For sports, I like this spacer from Amazon. The upper and lower lips prevent the spacer from falling out during activity. https://smile.amazon.com/gp/product/B0734KRL5N
One way to avoid all of the above entirely is to run in a sandal like a Luna sport sandal, but that is also flat and as you've mentioned earlier you prefer a lift.
Good luck!
My bunions stopped advancing when I started wearing toe spacers. The best toe
Sounds like you have a bunion. You could try using toe separators to help fix it and possibly might not ruin you next pair?
This is the kind my brother uses: https://www.amazon.com/dp/B0734KRL5N/ref=cm_sw_r_cp_awdb_imm_t1_MG1TD3AYDVK12G5EY53P
Povihome 10 Pack Toe Spacers Separators, Bunion Corrector Gel Orthotics (Updated Soft Version) for Bunion, Overlapping Toes - L Size https://www.amazon.com/dp/B0734KRL5N/ref=cm_sw_r_cp_apip_nZjtxbiv3IBG4