I have a semi feral who I cant get near and the only way of getting her in a carrier is to trap her in a corner and it takes me forever.
I shut all doors up stairs and all the doors downstairs except between the roonm she is in and the hall. I try usally unsuccessfully at the first attempt to block up the stairs!
As she will run if I get close she will usually run into the hall where I use the cage with door open covered by a towel to corner her............also need a piece of hardboard to block up other side cos she panics and cries terribly.
She will ytry to jump over in her panic but once she knows she cant get out she freezes and lets me stroke her and I try to manoevre her into the cage...........I cant pick her up cos she is heavy and very strong and can escape to easily. My vet who is very good with cats said never to scruff scared cats cos it makes them worse.
I always feel so bad doing this cos I know she is very scared and I get very stressed cos never know whether I will succeed or not. She used to hate me for weeks after but this year she got over it in a day or two.
The only advice I can give is if you decide to trap, make sure you have every detail planned in advance cos if they find a small place to back into that makes it very hard .
Another way if your cat is not as big and heavy as mine is that if you can get them sorter in the lying down crouch pose then quickly wrap a towel round them , making sure their legs are safely tucked in , and then lift quickly and put in the carrier.....that would be the recommended way of doing it , cept I cant get closer than 3 ft to Sasa.
Good luck