For a campaign I'm currently involved in, due to a plot event a cleric is interested in converting classes to a DS Sorcerer (basically he discovered his powers aren't from his faith, but from his blood). 

I want to homebrew a revised DS subclass to fix some things that are 'weaker' about it (like add a class spell list), and I'm wondering: is it possible, in DnDBeyond, to change a spellcasting modifier in a subclass?

Sorcerers use CHA as their standard, and Clerics use WIS - I'm wondering if it's possible to design a subclass that uses a different modifier from it's base class. For ease of transition!

Thanks. 

Yup.

Under Basic Information set the “Spellcasting Ability” to Wis and [SAVE CHANGES] and that’s it. Easy peasy, lemon squeezey.

To be honest, Divine Soul having full access to the Cleric Spell list is pretty baller, if instead gave them an “anti-spell list” where they had a couple of additional spell that don’t count as “known,” but let them prepare those spells every day like a cleric and it really does the trick IMO.