How does Arms of the Astral Self work with Strength ability checks and Saving Throws

dnd-5emonksaving-throw

Way of the Astral Self Monk has a feature called Arms of the Astral Self. My question is about a specific section of it.

You can use your Wisdom modifier in place of your Strength modifier when making Strength checks and Strength saving throws.

So what I'm wondering is if it makes Strength (Athletics) Wisdom (Athletics) or just uses the wisdom modifier but is still classified as strength. Also, if it makes strength saving throws wisdom saving throws, so if you have proficiency in wisdom saving throws (but don't in strength) do you add your proficiency bonus or not?

Best Answer

The only thing that changes is the modifier.

You have quoted the relevant portion of the feature text. Notably, the only thing it tells you to change is the modifier used. If it actually changed Strength checks and saving throws, it would instead read something like:

When making a Strength check or saving throw, you can instead make a Wisdom check or saving throw.

You are still making a Strength check or save, you are just using the Wisdom modifier for the purpose of calculating the outcome.