I watched the clearance maternity sections of my favorite sites for a week or two before I bought anything. Just like baby clothes, i found that there was little rhyme or reason for full price vs clearance price differences in items. If i was flexible about print i could get the same items at a fraction of the price. I also hate returning items so I just bought stuff on clearance to try for sizing and occasionally went back and bought more in prints I liked better.

For pants, i bought my professional structured pants from old navy that were on sale. I bought target's isabel and Ingrid collection for softer pants. I have no recommendations for leggings.

For shirts I bought the Torrid Harper shirts in different colors and a few sizes. They gave me plenty of room to grow and had tons of prints, some on clearance. If you're plus size and havent discovered them yet I highly recommend checking out an in person store. I bought the undershirts/tanks from kindred bravely when they were on clearance.

For shoes I recommend the sketchers slip on sneakers. They were a little bit of a splurge but my feet are well supported and they are easy to get on and off. Skechers Women's Go Walk Joy... https://www.amazon.com/dp/B071S2NX3G?ref=ppx_pop_mob_ap_share

I bought one dress from amazon that I love (I will post the link in the comments) and I invested in peel and stick fabric tape to change hems on items that were too long. I'm short so you may not have that issue.