The new LT app (word plugin) doesn’t have an option to only check selected text. This makes LT unusable for me. I hope, it is just a handling issue on my side and I simply could not find the option anymore.
But actually for me, checking with LT always goes through the entire document.
LT: Premium subscription
Word-Version: Microsoft® Word for Microsoft 365 MSO (Version 2408 Build 16.0.17928.20114) 64-bit