Use the crease function in Zbrush to keep those sharp edges in your block outs ready for sculpting.
Using Zbrush2023. If there is anything you'd like a clear quick tutorial on please let me know in the comments.
You can find me on all socials under ItsPaulTodd
If you'd like to support me then I'll have upcoming models for sale and potentially a Patreon for more in depth tutorials if there is demand for one.
Available for hire, please drop me an email.