It’s difficult to do something completely different under time pressure! Take them pressure off a bit. Lots of stories about it (little princess, Lola etc etc there are tonnes on amazon). Don’t comment on how well the character is doing etc or go overboard, just calmly read it. To encourage her to sit a bit longer on the potty and relax you could try asking her to stay on while you read a story or similar. Just keep repeating every half hour - “now it’s time to sit on the potty and see if a wee comes” etc. If it doesn’t, it doesn’t. My DD used to get a sticker when wee happened. We also did a couple of bare bottom days with potty very close to hand so that if she suddenly realised she had to go I just grabbed her and stuck her on.
Even if you’re very relaxed, they can find it stressful. My DD would sometimes get really cross because she knew she needed to go, say on the potty and then couldn’t remember how to let it go. Cue an extremely cross toddler who couldn’t wee until she calmed down.....
If she’s getting stressed about it, leave it a few weeks so she can forget the stress a bit and then try again.
We had a big battle with poo later on (if she held it in for any time at all, she’d then seem not to know how to let it go! Horrible constipation...), but if your child wants it to work and you are relaxed about it, wee doesn’t have to be too bad.
There’s a whole board on potty training if you want more support, try there.