Vibhuti means through which potency of Lord is expressed. Bhagvad Gita 10th chapter is itself named as Vibhuti Yoga and we find several descriptions about Vibhuti of Lord there like:
आदित्यानामहं विष्णुर्ज्योतिषां रविरंशुमान् ।
मरीचिर्मरुतामस्मि नक्षत्राणामहं शशी ॥१०- २१॥
Of the Adityas I am Vishnu, of lights I am the radiant sun, of the Maruts I am Marici, and among the stars I am the moon.
वेदानां सामवेदोऽस्मि देवानामस्मि वासवः ।
इन्द्रियाणां मनश्चास्मि भूतानामस्मि चेतना ॥१०- २२॥
Of the Vedas I am Samaveda, of devas I am Vaasava, of the Indriyas I am Mana, of the beings I am their consciousness.
रुद्राणां शंकरश्चास्मि वित्तेशो यक्षरक्षसाम् ।
वसूनां पावकश्चास्मि मेरुः शिखरिणामहम् ॥१०- २३॥
Of Rudras I'm Shankara, of Yaksha I'm Vittesha , of Vasus I'm Pavaka and of mountains I'm Meru.
And so on. As I discuss in my answer here, Brahman is equated to be everything of this universe. Like SataRudriya states:
Salutations to him who is chariot itself, maker of chariot, rider of chariot, charioteer, horses and lord of horses.
Likewise as I discuss here, Shiva Purana states:
ब्रह्मादितृणपर्यन्तं यत्किञ्चिद्दृश्यते त्विह ।
तत्सर्वं शिव एवास्ति मिथ्या नानात्व कल्पना ।।
Right from Brahma to the twig of leaf, ie . Everything in this Universe is Shiva himself. The concept of manifestation is not real.
So, Brahman is equated with everything of this Universe. But still for describing Brahman he can be described through his various Vibhutis which are present in this world.
Various Vibhutis of Lord Shiva are stated itself in Yajurveda Sata Rudriya Hymn. But, are there any instances in Mahabharata where Vibhutis of Lord Shiva is spoken?