Brake pedal goes to just before the floor before it catches

This is why brake fluid is a thing

I have bleed the lines with fresh fluid from passenger rear to front driver and still having the same issue

Could be low on brake fluid or the master cylinder may need replacing.

Master cylinder was my next move??

Be sure and bench bleed a new master cylinder before installation.

Some say to do it that way and others say do gravity feed and plug the lines??

After you bench bleed the MC and install it you can try a gravity bleed.

Installed MC and bench bleed and bleed all the wheels in order from the farthest too the closest and still the pedal goes to the floor..

Just changed pads on my 2016 subaru outback and same no pedal happened. Thinking of installing a master cylinder but now unsure. Did U ever figure it out?